Where to trade Bitcoin to USD bank deposits for mining company

[PeaMine]

I was curious, if you were to start a mining company just buying a bunch of miners and paying all the expenses of running them as well as maintaining them yourself, how should you go about this?
They are wanting to report it on their taxable income, and claim the miners and electric as expenses.
My first thought was Coinbase, but it seems there is a lot of debate going on about major exchanges currently.
They also might want to eventually run a website allowing bitcoin payments to a wallet and holding but eventually cashing in as well.
Thanks for all the help!

[PeaMine]

Someone suggested Malta as a country to register the mining operation with, though still curious about which exchange is currently most trusted and healthy for Bitcoin in order to pay the electric bill.