The equipments themselves
The Air conditioning units
The electricity that you had to pay
How iare you going to return your btc to btc ?
Tell me something i don't know ?
Maybe you're counting all of this in USD ?
That said, nobody is really expected to build his own datacenter in his basement (especially in a hot environment), as it will be more expensive than simply hosting them in a Datacenter in cooperation with spondoolies.
That is why there will be special long-term contracts available, of which the conditions for the WA datacenter are already available (290$ per month including space, cooling, security, professional service etc.)
Mining, especially when using high power equipment, was never a cheap get-rich quick scheme... and you always needed to pay for cooling etc. if you live in a hotter climate.