Topic: Safest way of long term holding (Read 855 times)

if you want to be safe in the long run and you don't want to use a 3rd party wallet you can choose another option. there are nano ledger and trezor as hardware wallets that are able to secure your assets in the long term. in 3rd party online wallets there are still risks even if you have kept your password or private key correctly and safely. So, in my opinion, the most important thing is how you keep the password or private key for your assets, it's your own policy choice

I use Trezor, Trezor One supports various types of digital currencies such as Bitcoin, Dash, Dogecoin, Zcash, Litecoin, Ethereum, and others. Of course this flexibility is widely used by users who trade more than one digital currency. The security form of Trezor One continues to be upgraded by collaborating with third parties namely Electrum and Copay. Please note that this Trezor One is not a software, application, or a Bitcoin Wallet wallet site, but is an electronic hardware.

Forget about it for a long time. Because if we keep it in mind that it's our asset, we will be brought in a lot by the media who want to damage the price of what we invest.

I think the safest way to store your holdings in btc is by keeping them in cold storage. In this way, hackers won't be able to make their way to compromise your funds in traditional means of hacking just like what most of them do. It's better to put your assets in an offline computer, flash drive, or hard drive to secure it won't be stolen. While this proves to be one of the most efficient ways to secure your cryptocurrencies, securing in cold storage has its advantages as well such as deteriorating of your chosen cold storage over time (e.g. computer), so you should do your best to maintain it well in the duration you plan to hold and store it.

Indeed. If he has many potential coins, his waiting time will be worth it in the future as he will make a lot of money or a big profit. But most people do not know how to pick the right coin to invest with their money and only follow other people's suggestions. People are disappointed holding their coins for a long time because they do not see the price increase after some time and that is because they do not research before they buy the coin. But suppose he only invests in bitcoin and uses separate wallets such as hardware wallets. In that case, he will not have to worry about his investment value because, in the future, the bitcoin price will be more expensive than today.

but it all also depends on the assets you save. holding long-term for a new project is a gamble. because the project could run for a long time according to our plans. it could also be that the project will stop its development due to a problem.
maybe it would be more appropriate to hold long term with the right assets sure to be profitable in the future. because we do not know the market conditions in the future. can also we come back when the market in the mouth of the bears.

I totally agree that long term holding is safest way it can be secure future with long term investing because near future price will go high and it has solid safety and security in digital assets. For safest side using a hardware wallet also known as cold storage it is most secure method for storing cryptocurrency.

I see there are some of the best ways to securely store bitcoins.
In my opinion online wallets are no more secure and faster in transactions. Online wallets are also known as "hot" wallets. A hot wallet is a wallet that runs on an internet-connected device such as a computer, cell phone or tablet. This way of storing can create vulnerabilities because these wallets generate private keys to your coins on these internet-connected devices. While hot wallets can be very convenient in how you quickly access and transact with your assets, they also don't have maximum security.

Thank you, much appreciated for the kind words.

I don't think too many OG who got any advice in 2010 or 2011 have kept their coins if they got any back then. I would be safely retired by now if I had kept any coins I got back then, or invested in some random site and kept the profits instead of spending them. But some of us have to buy that first pizza, or that miner, or that sock, or test it out on some platform ... And some of us actually lived on bitcoin earnings ...

My current best long term storage for bitcoin involves using Electrum and making backups of the seeds and keeping it all offline and cold. If I ever get around to having more than a few million dollars worth, it will all be migrated to multi-sig (still using Electrum) and several separate physical devices.

Version 22 of Core wallet came out recently, but I would wait some time before upgrading the main node. If you have back up nodes or wallets for testing purposes, you can probably upgrade that immediately and see for yourself if all works okay.

It would be best to buy a hardware wallet for your cryptocurrency assets so that you've full control over your assets. However, it doesn't mean you have a hardware wallet you're not prone to getting hacked or losing assets. It still depends on how you handle your assets well and how cautious person you are when it comes to transactions but ofc having a hardware wallet is the best thing to do for me.

There is no safest way to store your crypto in the first place. Safety depends on many factors: things that are suitable for me can be absolutely inappropriate in your case. In most cases, however, people tend to keep long-term bitcoin and short-term bitcoin separately. You usually don't want your long-term investment, your billions in bitcoin to move back and forth. You'd rather keep your keys on an indestructible metallic thingy or something like that than on your smartphone that will die should a nuclear explosion happens. You don't need a hardware wallet as a long-term solution because your plan is never move coins anyway and there is still a backup of your keys that should be kept safely. However, you can utilize your hardware wallet as a safe generator for your seed, the secret set of words that can later be stamped on a metal plate. Also, a hardware wallet is probably a perfect newbie-friendly solution for short-term transactions.

There's no perfect way of long term holding and I've come across this conclusion after years of crazy thoughts around cold storage airgapped holding solutions. In the end, it's about everyone's use case:
. do you want your heirs to be able to access those funds? then most paranoid solutions won't work;
. do you want that your coins will die with you? then go for it
. do you want to wake up one day, having forgotten how to retrieve your keys and being unable to access your wealth? that would be a nightmare!
Sharing is caring with your loved ones, that's what I did.

In practice, you don't have to enter your private key manually when it comes to desktop or mobile crypto wallets - private keys can be protected anyway if such a wallet is password protected. Of course, it is safer to have a special device that keeps private keys in an isolated environment, but even then there are risks that something could go wrong. An inexperienced user may fall victim to clipboard malware or fake Trezor/Ledger software/site.


It makes sense, I bought my HW just then and I can’t say it didn’t pay off. However, older models are quite cheap, and there are still opportunities during the year when discounts appear - so you just need to be informed and not miss the right opportunity.

I will also vote Trezor and Ledger. You can use a separate computer or store coins on a paper wallet,
but there is a risk of losing coins when you download a jailbroken wallet or your private key is stolen.
A hardware wallet does not require the user to enter private keys on a computer.
And the price of the hardware wallet is small, but it is better to buy with a discount on Black Friday.

Try to buy hardware wallet because this is the most advisable way to store your coins in a safe place.

The safety of your coin depends on how careful and responsible you are as a bitcoin holder and investor.

It is really not safe to become confident storing all your coins in one place and not maximizing the advantages of the existence of hardware wallets like ledge nano, trezor, and other hardware wallets.

The 1Feex and 12ib addresses prove that it is possible to store things long term.

As for random, a random number generator is mostly fine, except these things aren't random. You need a little bit of entropy. from any second source
A little bit goes a long way. This could be adding in a few characters to those random numbers that you personally have come up with.
A few bytes changed makes it more random than a computer.

A much more important thing is not using the default generated address from bitcoin core.

Every key has like 2^99 addresses that can be associated with it.
Bitcoin core uses the first one or two these possibilities. (I wish core was programmed so that you can put in your own
magic number / k value? Random is unnecessary here. I forget what it's called. Ideally you want this number to be very large..)
Using the default address generated by core and its low k means that all an 'attacker' has to do is match their key with few possibilities of addresses.
Still a lengthy process, but much less lengthy than any other method.

Python software is pretty good at generating addresses from keys, and you can easily look through most of it to see that the code doesn't open internet connections.

This can generate a wallet-import-format or wif, https://github.com/crcarlo/btcwif/blob/master/btcwif.py , although it is older.
pybitcoinwallet can generate addresses from this wif. Check that your software can make more than one address from any given key or wif.

import btcwif
key = ''
wif1 = btcwif.privToWif(key)

Separate out your keys into more than one to avoid the hopefully unlikely loss via any number of means.

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2) I do not want to use any 3rd party software as a wallet. Suppose I just store my private key on a piece of paper and later transfer coins into it using exchanges. Would that be a valid transaction and allows me later to spend these coins? Is there anything else I need to store together with the private key (like the hashed transaction number in transaction_input in the blockchain? ScriptSig?) I really want to avoid 3rd party software because it might be obsolete in the future and data can be degraded. (Say if I use some sophisticated cold wallet, I may experience hardware degradation in  10 yrs, no one at that time used this software, programmers 10 yrs ago cannot be reached, and any trick in coding or encoding in the original version becomes obsolete. I would be a consumer rather than an investor of BTC...)
 

What's a wallet?

You don't need any software to save bitcoin since it's distributed across miners and nodes on the net. It is much harder to do without software though! You can import your key when ready into bitcoin core, but you will have to rescan the entire blockchain, which can take a while. I recommend trying it out with a small sum first. You don't want to make a mistake here. This test takes a long time.

Try not to spend your coin after transferring to your wallet to not give out your public address, although 12ib proves again that you can be 'safe' since it has several transactions out.

Degradation of code, software, and economics will always be an issue. You may want to keep an old computer that can use bitcoin core software. The internet and miner protocols shouldn't change over that time, but who knows. If quantum computing takes off in big ways or certain fakes have their way, then very old transactions may one day become invalid, so ideally you shouldn't become completely disconnected from your wealth for too long in the event of the unforeseeable.

The safest way of storing your assets is a cold(hardware) wallet. It is not connected to the Internet. It represents the USB-device. The most popular are Trezor and Ledger. You need to remember your private key and password for this device. So that even in case you lose your device, you will be able to restore access to your assets.
Don’t hold your tokens on exchanges’ wallets, only such sums of money that you are going to use there. 

One way to secure your bitcoin in the long term is to have your keys. HW might help, but there are doubt that it will become obsolete if you just leave it without keeping up with regular updates. If you are a long term holder, it is your obligation to check your asset and storage wallet regularly and you may have to move all your asset to another wallet every 6 or 12 months. Another best advice is, don't put all your eggs in one basket. Make sure you have 2-5 or even 10 HW if your bitcoin are worth millions of dollars.

We invest in risky asset. Apart from fluctuating price, the security of your asset storage wallet will be your sole responsibility. If you want to get good security, then you should check it regularly. I know this isn't the best advice, but at least I think it can help people who want to get security for their assets.

The dump down to the ground is next to impossible, bitcoin has come a long way and I don't think that bitcoin is going to go back to some specific low numbers ever again. Well, you got to be ready but if you really are a long-term hodler then it wouldn't faze you if the prices are going down really bad.

can you mention what site provides the service.  I think I'm interested in investing there.  because I was once deceived by the bitcoin interest system and it ended up being a scam.  please provide the link.  thanks

It's good to hold but you have to be ready for the consequences and you have to keep in mind that the Bitcoin market can be anytime pumped to the sky or down to earth.

Always good knowledge coming from you, if at least one noob will start dealing with bitcoin the right way after your post, you're to be thanked!
Buy, forget and store securely your bitcoin has long proven to be the most effective wealth advice for new bitcoin holders. I wish I'd have been given that advice in 2010

Agree with @Dabs, don't just store your btc on a cold storage and walk away for long, occasional update yourself with latest happenings in the news about btc will help keep the person up to speed,  anything can change within the time you are absent,
Between the cold wallet storage should be kept in a cool dry place with the right temperature, and always try to inspect it at intervals to ensure it is working properly.

Another protocol for you to follow, my suggestion or recommendation, is to not simply store in cold storage and forget about it for 10 years, unless you are incapacitated or unconscious, is to simply look up and research the current events and keep updated.

The core website, any of the major bitcoin / crypto news websites. To keep up with news about any soft forks, hard forks, new address formats, ... I mean, it would be a good idea to switch from legacy to nested segwit, or skip directly to native segwit... and in the future there might be a new format for taproot and schnorr as that is being proposed right now.

Once a year, review your coins, and study how to transfer them to a new address safely.

Ideally, you would be contributing to your stash often enough that you can include this as part of your strategy for long term holding.

There are people out there who buy for their retirement every month. Once a year isn't too much huh?

This is in addition to doing anything to make sure the wallets are indeed cold storage, the computers or hardware you use have an air gap and all the other stuff mentioned by everyone else.

If your devices compromised because of exposure to elements then probably you are doing it wrong in terms of storage. Not every time capsule needs to be buried underground. Also if you worry about humidity and moisture damage then you should just buy some silica gel desiccant.

You Don't know about Ledger wallet? FYI you can store your coins there for very long time without any trouble in Typhoon or whatsoever .
It is our style how to keep it safe, even in paper or in metal the same process, we need to keep out from reach of others.

Another one would be dusts as well upon the increased temperature as you mentioned. I guess keeping it in a really secluded container like trunk box or at least safe box would lessen the possibility of dust build-up.

Mine was scrapped because it just doesn't show the colors properly anymore.

Keeping the Private Key in that piece of metal is a good idea as is the metal plate that some hard wallet products provide.

But it also needs to be supported by the best place to store it. do not carelessly save the valuable private key. You will still need the metal canister and store it in the ground like a treasure.

When you say it like that, it seem exchange were an option before but since from the very begining they haven't been an option then you should go with the statement, Exchanges most especially the centralized ones are bad for the industry.

Exchanges this day have found a way to convince (actually decieving) users into trusting their funds with them. They constantly have engaging ads that'll make you want to engage with them 24/7 with your funds. They have Crowdfunding in exchange IEO, staking, Mining and the most recent which is farming.

They also present themselves as a safest way to store the variety of coins you would had picked interest in investing into them.

every action has a risk not all coins are not safe to invest in the long term for example ethereum everyone who holds ethereum coins in the long term they can profit a lot. My advice, if you want to hold coins in the long term choose the top 10 there is a chance that you will get a profit.

No way there's a safe long term investment, it always comes with a risk no matter how careful you are. However given how crazy the market is, even a useless token is a good investment. Long term holding will surely be fruitful especially now that the cryptocurrency is now being recognize around the world.

There's no safe place to store bitcoin mate especially long term wherein even you make backups through your computer or in any device its still useless because you know there some tragedy that sometimes happen in our life without knowing.. For example those that really cause totally damage especially super typhoon.  How can you assure those things where you stored your back up are really safe?.. I think its impossible..

Actually i saw some user here shared his idea how to save our private information on such incidents.  And it was engrave in a piece of solid metal which is a good idea and yes, i believe that's the safest way what i mean is even no matter what happen because its unbreakable and its up to you where to keep it.

For me I think the best way to invest and keep bitcoin safe is storing in a cold wallet, and by doing this you really need to keep your keys safe, I know some people will be like what if i misplace my keys! Well I think what is very important to us we shouldn't play with it or keep it carelessly, even if it warrant you storing it in multiple places. Keeping your asset in exchanges might be risky tho, anything which happens to the exchange affects your funds, and talking about hard wallet! I ain't used to it which makes me prefers cold wallet for keeping my assets safe.

It is not just a matter of use, damage of some kind can also occur due to some external influences such as humidity or exposure to increased temperature. When you talk about the time capsule, then it first occurs to me that you might bury the device underground in some sort of protection or you might even use concrete and hide it somewhere in your basement. At least when it comes to Ledger, I know that these are not some premium materials (at least as far as the S model is concerned), and that these devices are not made to last indefinitely.

As for other devices, I also have a TV that still works -  it's over 15 years old, and who knows how much longer would have lasted if the digital age hadn't sent it into a well-deserved retirement.

It wouldn't break down if you rarely use it, we still have a television in my home that is around 6 years already so I think that a HW will last that much longer. Maybe I will worry about the other things about storage when I already have it in my table but right now, I think saving some bitcoin is top priority.

You don't need any advice because you have already pointed everything that needed for safety investing and also you mentioned the wanting for Bitcoin and for me that is the safest coin that everyone can trust to invest their money.
so what are you waiting for mate? Buy bitcoin now and start holding in your storage before its too late and the value climbs up to 100k soon.

Talking about the safe way of storing your Bitcoins that is where hardware wallets take part because it is away from the internet so there's a less chance for it to get hack and stolen by anyone unlike web and mobile wallets. However, since it is a hardware wallet is it more prone to physical damage that is why you must take care of it and placed it where does anyone doesn't know and away from the place where it can be easily destroyed. Another way of holding your stash is to diversify your BTC in a different wallet so that even if one of them got destroy or hacked, the loss wouldn't be that much.

Maybe it would be good to read all the posts from the beginning, there are some good observations on the topic of hardware wallets that would be worth considering. As much as HW has advantages, you should also take into account the fact that these are electronic devices that can break down at any time - and then only backup can save you. Consequently, if you already have an idea to store something in a time capsule, it could simply be a backup (seed) generated in a safe environment using Electrum.

Probably that's the best by far, I plan to buy one this year and fill it with bitcoins and leave it on a time capsule and let it stay there for five years and if the prices do go up in the future then lucky for me because I will get a lot of profit.

The safest way of holding for the long term is using a cold wallet or hardware wallet, when we are planning to hold huge money for the long term then we should secure it by using the safest crypto wallet and that is a hardware wallet, those people who are holding huge amount of BTC are sreuly using a hardware wallet as well because there is no possibility that it can be hacked because there is no need an internet to access it, just make sure that you will place your wallet to the safest place where it cannot be burnt out and get wet.

hardware wallets such as the nano ledger or trezzor are the best for you. I as a nano ledger user for 2 years feel safe and there is no loss at all it makes our assets safe

For any long term holding project you need a best secured wallet. Wallet should not be accessed by anyone. These measures secure your fund for any duration then you can hold it for long term or any duration you want. Wallet security keys or anything should be placed in proper way to not get lost forever. Security is key for long term holding

For long term investments you need to use a secure wallet access to them cannot be shared with anyone. Keeping your personal information and wallet password safe will keep your long term investment safe there are many wallets online but not all of them are secure hardware wallets are really much safer and much harder to hack. Also if you use the 2 fa code in the wallet to keep it safe no one will get the wallet information.

You dont have to be paranoid and worry too much. You are just making things so complicated by those "What if's". If you have your ledger Nano S or any kind of trusted hardware wallet, as long as you keep your private key with you and never share it with others, then your long term hold bitcoin will be safe.
 
 Those online tools can be useful but unsure security and can be hacked so if you arent careful enough to ensure your private key , then it has a possibility with those what if's to happen.

It is a good idea to hold Bitcoin to wait for the right moment. If you held Bitcoin 10 years ago until now, then you are already a billionaire. Keep your Bitcoins in a secure wallet to avoid account theft. The way I usually keep my money is by using a secure system.

To maximize holding, we must maximize several elements including security, strategy, and mentality. for security, a hardware wallet is indeed the best choice. online wallets and the like can also be maximized security by using double protection and wisely using the internet. Regarding strategy, everyone has a different way, there are those who buy at once when the price is still low, or buy regularly and accumulated, please choose which one you are able to manage the risk well. well the last one is mental, we know that cryptocurrency volatility is very high. mental holder is tested when there is an increase and decrease in price, there will definitely be a dilemma.

that is why we must be very selective in choosing coins or tokens to hold, make sure it has strong market power and good fundamentals, such as BTC, Eth, bsc, etc.

This topic has touched a very good point. Because still, many people in this market do not know exactly what to do to safely hide their investments. When I read this subject, I realized there were actually things that I did not know. I used to think hardware wallets were secure, but I noticed the possibility that computers will not use the same connector in the future.

The safest way to hold and own control on your keys and coins is by using a hardware wallets like Trezor,Nano ledger and other hardware wallets out there,
But I highly recommend any of the two that I've mention.
Just make sure that you would keep them updated from time to time.

buy a hardware wallet like the Ledger Nano or Trezor and start moving your bitcoins into that wallet
but I'm not sure this device will last for the next 10 -20 years because any technological sophistication can happen
What's more in a virtual world like this, cyber crime is very easy to take your assets without us knowing who did it
the safest place to store in the form of fiat and save your funds on bank

The technique in investing long-term is to create a safe crypto wallet where you can store or keep your Bitcoins and other coins, then buy your prefer coins that you want to keep for a year and more. After that, keep your private key then uninstall the wallet. This works for me as I can’t open my coins and check them from time to time. I just buy and forget.

I am happy to hear that you won't be blindly investing but was able to learn the basic mechanics of Bitcoin. I've seen and heard a lot of people who lost a lot of money by just following the hype. Just be weary of the market correction and you're all good.

In 20 or more years, there will be a new technology that will better from that company.
Do you want to use the old technology while saving a huge bitcoin amount in the old wallet? I bet you do not want to.
We always need to evolve and not just use the old one if a new invention comes out to give us a better experience than before.
If I have that experience, I will not keep it in the same wallet, especially if the company has gone out of business because that will be my responsibility to take care of my funds.

I'm not sure if generating private keys using a third party software and tool is safe enough because there is anyways the risk of getting scammed by saving the private seeds by the tool. The random generated private keys are much better and safe to use. you can also write the key in a piece of paper and put it somewhere safe.

Generally, in my own idea if you do have more than 10K worth of bitcoin, the best thing you can do is to buy a lager nano wallet and do not trust the software wallets because there is always the risk of getting inflected by malware. Also, people say don't put all your eggs in one basket, so I would suggest you to don't put all your bitcoins in one single wallet and try to use multiple wallets. For example, I do have a wallet for long term investment and it's untouched for the last 4-5 years, also have another wallet I use it here on forum.

First and foremost, you yourself are the one who has to persevere and not sell prematurely or lose confidence. An example: if you buy a vehicle, it loses value as soon as it rolls out of the garage. In contrast to Bitcoin, from which an enormous increase in value is expected.
One of the most popular comparisons on an old Twitter thread was the one with Bitcoin pizza man Laszlo Hanyecz, who paid 10,000 BTC for a couple of Papa John's pizzas in 2010. A sum of BTC that would be worth hundreds of millions of dollars today.

No, all you have to store and keep safe is your private key. All other information related to transactions like their hashes, inputs... will be saved on the blockchain (publuc ledger) so you don't have to worry about them.
However, you should consider saving the public address related to that private key as well. You don't want to have to derive it each time you request a payment or check your balance!

I have heard of the Glacier protocol (https://glacierprotocol.org/) for storing bitcoins in cold storage which involves a couple laptops and USB sticks. I don't know how secure it is though, because I have never tried it (and most people here aren't in a position to order $1200 worth of computer equipment just for this task since it requires factory-restored devices).


They are not rumors. They are real.

Right now I can download Pollard's Kangaroo program from Github and use it to break private keys searched in small (<60) ranges. A cluster of several dozen GPUs can break private keys with ranges as high as 115 bits.

Actually the public key isn't even needed, the same GPU clusters can theoretically brute-force RIPEMD160 hashes (ie. your address) with smaller-sized ranges.


Paper wallets are complicated to set up and too easy to make a mistake while printing/engraving the private key. What happens after that is you forget or lose a couple characters of the private key.

Paper wallet generator sites have never been secure (cf. BitcoinPaperWallet) and you never know when or if they'll be sold to somebody malicious.

There are a lot of tools for offline generation of paper wallet. You could even disable internet on you computer to do is safier. Or use one-time VM for generation of keys

I was actually referring to Danny's statement.

But yeah, it was just a suggestion.

There is nothing to disagree about here, OP wants a wallet that he generates himself, not about staking for interest on crypto custodial service companies, these services can not be discouraged, but does not fulfill the purpose of bitcoin which is privacy.

I agree with your first statement. Not your keys, not your Bitcoins.

Of course there's risk to such as it's happened before but it's a suggestion in case the OP might be interested. I myself have parked my coins with such FI and have enjoyed the yielded interests. Unlike normal FD accounts with stricter tenure (e.g. 3 months), the terms are way more flexible.

So let's agree to disagree.

I'm saying that if you don't have sole control over the private keys associated with bitcoins, then you don't have the bitcoins.

In the scenario you are describing, what you have is a promise from someone else that they will spend THEIR bitcoins in the way that you ask them to.  It's up to each individual to decide just how much trust and faith they want to put into any particular entity making such a promise. Will the entity be hacked?  Will your account at the entity be hacked?  Will the entity file bankruptcy?  Will the government shut down the entity? Will the government confiscate the entity's assets? Will the insurance company have enough assets to cover 100% of any losses?  Will ANY and ALL losses be covered by the insurance company, or are there conditions that must be met?

You can put your faith in promises if you like.  I prefer to put my faith in bitcoins.

I was referring to financial institutions that offer such services such as Celsius Network, Blockfi and the Nexo.

Are you saying that those entities are a scam?

I suppose I meant both.

Need a derivation path to derive all the keys, but also need to be able to generate the addresses from those keys for use in receiving the bitcoins.

of you can use the old school https://bitcoincore.org/en/download/ just save your private keys and store your coins for a long period of time. there were rumors that if you make a transaction using the same address you use to conduct a transaction, it would mean your public key will b exposed and that a quantum computer might just be a threat and can also expose your private key. not sure if it's possible but store your coins and not use the wallet afterward. not even once.

Don't you mean BIP-32? BIP-44 is just suggesting a certain derivation path to be used by wallets not the algorithm to derive the child keys (and their corresponding addresses).
We have a couple of other similar BIPs defining standard derivation paths such as BIP-49 and BIP-84

With your explanation, I think you are guru enough to generate private key safely. There are different methods of doings this, you can decide to use a paper wallet website offline, like bitaddress.org in case you want to hold, you can decide to download electrum on airgapped device to generate it, you can decide to use a multisig wallet, you can decide to buy hardware wallets like trezor which is completely open source and private key generation on it is offline.

Like electrum, it is open source, there are ways you can even run it offline, trezor is also offline wallet. If a wallet is open source and its source code is available to the public, I think this is sufficient enough to trust the wallet.

Yes, it will be a valid transaction, but making sure you track the transaction on blockchain to be certain that the transaction is valid and confirmed.

It depends, if it is seed phrase you generated using wallet, the seed phrase is enough. If it is extended with passphrase, you will need to make a backup of the passphrase. If it is private key that was generated, and you encrypted it with BIP38 passphrase, you will need to backup the password used for the encryption.

Not your wallet that matters in this regard, what matters are your backup, your seed phrase or private key can recover back your wallet even on another wallet devices.

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What I think matter most is for means of private key generation to be open source, if you are expert enough, you can run iamcoleman offline for this purpose. Bitaddress.org is open source, electrum can be run on airgapped device and yet open source.

I have to agree with you that a 3rd party wallet provider for long term storage is not an option for me too. The constant updates and upgrades and firmware upgrades on hardware wallets is a total pain in the ass.  

I created "Paper wallets" on a air-gapped computer and I have used it for MANY years without any problem. Unfortunately I had to use 3rd party Open source software to create it, but as I said.. I have had no problems with it. Use bitaddress.org A Open Source JavaScript Client-Side Bitcoin Wallet Generator. (You can download the Github source code or just the whole script from the website to do it off-line)

Suggestion : Make several copies of the paper wallets and laminate them. (Store in different geographical locations)  

How sure are you that the hardware wallet will still work 20 years later?  How sure are you that computers 20 years from now will still use the same connectors? How sure are you that the wallets will still support 20 year old hardware wallets?  This does not sound like a reliable solution to me.


You think that computer and storage will still be running 20 years later?  You are willing to risk what might be millions of dollars on that possibility?


You should ABSOLUTELY be afraid to trust and be anxious when your bitcoin might be worth millions of dollars in 20 or 30 years, and you need a storage that will last that long.


And any criminals that break in, or any visitors that come to your house, or any workers (plumbers, electricians, delivery, installation, etc).  Also any government officials (police?) that decide to investigate your home.


It's cute that you are so naive. Not everybody has trustworthy friends or relatives.  Some people are stuck living with criminals or addicts.


And if you forget the password after a few years?


What if the "standard" method of seed phrase generation changes? Then how do you use your seed phrase?  You would need to find OLD software from 20 years before that can still run on the modern computer.


There are many stories of many people that lost access to millions of dollars of Bitcoin because they "did not get too much worries on everything that might hinder them".


Credentials are not enough.  You need to know how to use those credentials.


So it is advisable? Or it is not advisable?  You say both.  This is very confusing.


Ah, ok. Not advisable.  Thank you for pointing out what not to do.  This is not every helpful in answering the question of what to do.


Well now, that certainly sounds like a scam.


Well, I'm glad you cleared that up.  Then again, that is what a scammers would say, isn't it?


And in 20 or more years, when that wallet company has gone out of business, if that hardware wallet doesn't work, what do you do then?  This does not sound like a reliable long-term solution.

You can buy a hardware wallet such as Ledger Nano or Trezor and start moves your bitcoin to that wallet.
Follow the company's guide or the manual from the hardware before moving your bitcoin and read about how to protect your wallet from other people who want to steal your bitcoin.
As long as you do not tell people around you about having bitcoin and the hardware, you are safe because they do not even think about you have bitcoin.
Make sure you save the hardware wallet in the safest place that only you that will know.
Make a backup for your private keys, so you can recover the wallet and get your funds if something happens.
Finally, you should not feel too worried or freak about the hacker, the scammer, or others and make it as simple as you can, so you will not think that saving bitcoin will be too complicated.

Have you considered storing your Bitcoin on an interest account? You earn daily/ weekly/ monthly interests rather than letting it sit idle.

And if you are concerned about fraud, those service providers are insured.

Cold storage is more recommended to be honest just don't lose the needed credentials to access the wallet because you will be waiting for nothing. Storing it in a computer is advisable but given the lifespan of many computers, I don't think that it will be best for the long term because there might come a time when the computer gets broken either by accident or wear and tear, I highly discourage storing in computers, especially if the computer is not a brand new one and you are always clicking suspicious links.

The safest way to store btc are those cold storage. The hardware wallet would be the best example. However, obtaining hardware wallet like ordering it online would still not suffice to get the safety of your btc holdings.

In my opinion storing btc in an offline device like computer would be more safe having installed offline wallet in it. You should not afraid to trust this process and should not be anxious as what you have mention that it might be brute force by anybody wishes to gain access in it. The possibilities of having the access to your computer are only your family member or people living in the same roof and they can be more trusted more than anyone else.The computer system also can have added security features like securing it with password on specific drive where your btc keys are being stored.

The most important thing that you should have when you store your btc are they keys that include its seed phrase in which all keys can be disclose just by the seed phrase alone. This is all that matter and do not get too much worries on everything that might hinder you to get more btc in the future. Just remember the phrase "not your keys, not your bitcoin". So take good care of seed phrase and the keys to your btc holdings.

Bitcoin is an open source protocol.  ALL bitcoin software is "Third Party Software", unless you are going to do all of your computations with paper and pencil, you're going to have to use third party software of some sort.

If you are concerned that the method you use for key storage and for address generation may not be supported in the future, then along with your key information, you should store instructions for yourself on how to use that information.

Your best bet for generating trustable "random" data if you want to go to extremes is to roll dice.  You'll want a consistent method of rolling the dice, and a consistent method of determining which order to read the dice so that your human biases don't come into play.

After you've the dice enough times to collect 256 bits of entropy, you'll convert the dice into a Hierarchial Deterministic master private key. That way you can have as many addresses as you like, while only needing to go through the dice process the one time.  For the safest storage, you'll want to convert that Hierarchial Deterministic master private key into a 24 word recovery seed phrase.  If you are concerned that the "seed phrase" process may change (or go away) in the future, then you'll want to make sure that, along with the phrase, you store instructions on the process of converting the seed phrase back to a numeric master private key.

Once you've got your master private key encoded in a recovery seed phrase (along with instructions on how to convert back to the numerical value), the next thing you'll want to do is use the BIP-44 process to generate addresses. Again, you'll want to make sure you store enough information that you'll be able to repeat the BIP-44 process in the future just in case it is no longer a common process and you can't find any software that will do it for you.

There is currently open source software that will perform both of these processes for you, for example: https://github.com/iancoleman/bip39

However, that software may not be available in the future, or may not run in whatever environment you have access to. This is why I suggest making sure that you:
1. Understand these processes so you can re-create them (by hand if necessary).
and
2. Store instructions with the keys that explain how to perform these processes (in case you forget some of the finer details).

I am considering holding Bitcoin for the long term. I have learned a few basics about the blockchain and BTC mechanisms, but still unable to find a complete guide on how to safely store bitcoin.

1) How to generate a private key safely? Online tools are obviously undesirable as they might keep a back door on all keys generated. Similar reason for any library or packages even they operate offline (I cannot check if these keys generated are in fact following some predetermined sequence).

I can use a random number generator on an offline PC. But I am not a real 'hacker' and have concerns on whether any programming language can produce truly random numbers that cannot be reproduced (or say predicted) on another PC. They might all rely on some external factors (such as time) which greatly reduce the possible key generated and make brutal force algorithms possible.

Currently, I can only think of throwing dice for key generating but that cannot scale.

2) I do not want to use any 3rd party software as a wallet. Suppose I just store my private key on a piece of paper and later transfer coins into it using exchanges. Would that be a valid transaction and allows me later to spend these coins? Is there anything else I need to store together with the private key (like the hashed transaction number in transaction_input in the blockchain? ScriptSig?) I really want to avoid 3rd party software because it might be obsolete in the future and data can be degraded. (Say if I use some sophisticated cold wallet, I may experience hardware degradation in  10 yrs, no one at that time used this software, programmers 10 yrs ago cannot be reached, and any trick in coding or encoding in the original version becomes obsolete. I would be a consumer rather than an investor of BTC...)
 
Any advice?