Get brand new, most efficient miners available. If someone is selling his used device, it most likely means that it's becoming unprofitable.
not really, maybe he has bad electricity to sustain the mining in his house, but if you have a cheaper electricity than him it can still be profitable for you
so it depend, certainly i would pay far less if it is used, not like the beginning where many were buying at even higher price than the new
Used mining gear is usually totally overpriced. You can even find 0,3GH USB block Erupters for about 25$. Offers with fair price are the minority of the second-hand market.
Of course, you can consider doing the same thing - selling your gear with the price 2-3x of it's real value, and consider this income as a part of ROI
In general, recently released devices are more energy efficient and then profitable, than their predecessors. It will be ideal situation, if you could buy used miner right after introducing, for the price lower than you would pay for a new one. The longer you wait to get even recent model, the less time you have to make an ROI.
Some keep those up as collectors though. There are some who have collected every color on block erupters for fun. I did not do it on them but I did on compacs try to get every main version. So I can understand the collecting for fun.
Makes sense to me. Also, some people just want to be a part of mining community, they like the process and all things related to it - in that case profitability is not the factor to be considered. USB miners are very convenient and electricity costs are not worth mentioning, so they are ideal when you want to mine for fun
When it comes to mining you got the
1) Miners who want to see profits, the business miners
2) Miners who want to be part of bitcoin and mine it, but also earn back their investment, most of us belong to this group
3) Miners who want to be part of bitcoin and can accept a little loss.
4) The group who try to be one of the above (1 and 2) and fails
Only the business miners can achieve ROI these days.
The've got better prices both for PSU/Asics + electricty
It's getting harder and harder for hobby miners, the difficulty level is biggest factor I think. If we had 2-5 percent would be much easier. But these 10, or even 15+ are scary. Just look at this weeks difficulty it's scary high.
I think group 3 is pretty small. Most that run at a loss I think sell gear at this point. There is not a whole lot of reason to run at a loss. They might lose a little before figuring it out. There are some that claim they support BTC no mater what, and want decentralization. But most can not afford this luxury of losing money on a lot of gear.
BitFury has a new miner proposal to put 2MW miners into a container sized area. It is 12-16 PH each. So there will be no place for hobby miners in the future.
They have a rendering of it, that is far from having it. You can make a rendering of almost anything. But most of the big buyers I am guessing still have a data center set up.
Chances are they will not need to invest in this container, they will just need to swap old gear to new gear. I don't see this container being a big seller. When SP 30ish gear was new a company made containers and I think they got like 2 as proof of concept, but sales never caught on.
