Some of the crypto are not really in use. Many of them are just fraud so newbie should validate first any crypto to buy and use. Some are just good in their white papers but later on they will not commit on the writings but instead they will change it in favor of the team.
That's an important point. When you look at sites that accept crypto, it is bitcoin, ethereum, maybe bitcoin cash. In this thread, I am using bitcoin, but only as an example of the use of crypto.
A) How do we know the amount is what we want to send?
I Usually use the conversion tools like this awesome coinmarkrtcap tool;
https://coinmarketcap.com/converter/btc/usd/ to estimate the amount of BTC am going to send corresponding to the USD value of the package on the service site
If the BTC value is the actual value or almost the same value to some decimals as the one that has been read by the coinbase QR code, then I can go ahead and confirm the transaction.
Exactly. The site you are buying from could have intentionally used a conversion rate that was not fair.
B) How do we know that the money is going to who we think it is going to?
First, we get to check, the deposit BTC address on the service... We check and compare letter to letter or number to number to the address shown after scanning with the QR Code reader on the Coinbase app, If there is a perfect match better the addresses then we can go ahead and confirm the transactions
QR Code scanning using the coinbase app is actually safer compared to copying the address from the website and pasting it into the app. There have been cases of users getting their notepads hijacked by malware which changes the BTC coin addresses. When the victim copies the depositing addresses from the website, the malware simply changes the address to a different depositing address. If the unsuspecting victim is not vigilant enough and confirms sending the BTC without thoroughly checking the addresses, He loses his funds to the hacker.
Correct. That's the merit in copying the pay-to address to a 2nd device, but always check it. The QR code will contain the pay-to address, but it is not impossible that it could have been changed, either by a virus or website impersonation.
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Now, regarding this pay-to address. How would we know it is linked to the company? We'll handle that in the second example in this series.
