Who pays for the power?
The cooling?
Insurance?
Building maintenance?
Taxes?
Other fixed expenses?
I'm sure I could go on but you get the idea.
It looks good at a glance, but depending on all the costs involved you could wind up way behind.
-Dave
I'd just hand over all those expenses to the mining company. After all they are the ones running a mining operation in his building, so it's only fair if they pay for stuff like electricity and taxes. OP only pays for building maintenance (and building insuranse but that's strictly it).
But that is where it gets tricky.
Mining is a lot more abusive on equipment then being a warehouse.
I don't know what this building has for cooling but most units that were not setup for data center use are not rated for 24/7/365 use that will shorten their life.
Same for transformers. It's usually 75% (IIRC might be a bit lower) of rated for 24/7 above that their lifespan drops.
In most places the building owner is responsible for the bills if the tenant leaves without paying. They bail on 60 days of unpaid power you have to pay it.
And so on. As with everything YMMV and the local rules will vary on location but having people in the family and friends that own commercial property it's not always that simple.
Hell in the building down the block from where I work there was a business leasing space that managed to skip out on close to $150000 of gas and electric. They were using about $40000 a month so it was only a little over 100 days but still a staggering number since the landlord was only collecting $30000+CAM+taxes for rent.
-Dave