2) you buy a miner in about 5-6 weeks you have the same BTC and the ability to make more BTC if the price goes up or the difficulity goes down. Thats why these farms are rigging powerful mining units. Equiptment will be paid for and it will cost hardly anything to let it sit. However when the BTC price shoots up they can crank out milions of $$. Run your calculator at 2000 or 5000 BTC and see what you get.
Most of these miners will not ROI in "5-6 weeks" if it doesn't produce more BTC than you could simply buy on the market for the same fiat cost then when BTC price shoots up you will end up making less $$ and have to put in work to do it.