...with 4 graphic cards, ...2 on BTC throught nicehash,
how does this even work?
your GPUs are not even producing enough hashrate to be relevant when it comes to mining bitcoin! are you even getting paid?
I am not a miner but I suggest checking other altcoins for mining with your GPU, you may make a lot more profit than this because you need an ASIC to mine bitcoin. try visiting coinwarz and other mining calculator sites to get more information on this.
I'm not the best at economics and it may be heavily flowed, that is why I need you. Note of interest: I believe in crypto so I'm long-term bullish.
it all comes down to this and the way you think about it. I personally have no faith in any altcoin which is why I only have my long term investment in bitcoin but if you don't agree with my view then your plan is good enough.
as I said I am not a miner but I have thought about it. if some day I start doing it, then what I will do is that I sell as much to just cover the costs and keep the profit in cold storage. so lets say I earn 1
BTC per month and the cost is 0.9
BTC, that means I sell 0.9
BTC and keep 0.1
BTC (just example numbers).