I know hardware is a sunk cost, but you should probably put some amortization in there.
Where are you getting the USD1500 price tag, I've just done a quick search and I only found a bunch of S9 Miners (Bitmain Antminer S9) advertised for over USD6000 on Amazon.
https://www.reddit.com/r/BitcoinMining/comments/7jg14f/one_o...
the same analogy applies here, BitCoin mining is quite profitable, however hardware business is more reliable and in demand.