calculation is meh.
factor 1 power cost
factor 2 power amount
factor 3 power cost and amount staying stable for how much time.
if you mine in a home unless you have solar energy the power is likely not cheap enough to mine for profit.
ie mine solo mining for hobby and bragging rites if you ever hit a block.
Now lets say your cost is 10 cents to 20 cents a kwatt and you need some heaters in the winter
if true you could buy a used unit and run it down clocked for the winter months.
Lets say your power is over 20 cents forget mining except for a tiny solo miner like this
https://altairtech.io/product/hammer-miner-bc01-home-bitcoin-miner/now if you want to mine at commercial levels and do not have cheap power you need a host.
1) first rule for the host is he honest
2) second rule for the host is he honest
3) cost of power
4) cost of power.
if you want to mine at an honest spot my guy has been good for 2 years.
Nate at corex
https://www.corexhosting.io/this gear is $3550 270th
https://www.corexhosting.io/product-page/bitmain-s21xp-270tthis is hydro cooled gear 6900 550th
https://www.corexhosting.io/product-page/whatsminer-m73s-hydronow if you want to go professional and buy from above I will tell you it is marginal
the top unit burns 3600 watts an hour or 3.6x732=2,635.2 kwatts a months and power cost is about
243 usd the unit earns about 328.32 a month so 85 a month paid back towards the $3550 price of the gear
that is marginal a strong chance you will not turn a profit.
the second unit is about 2x on power and earnings which makes it very marginal
there is a strong chance you will not benefit from them.
mining is hard real hard.
it is not fast money.