If I had 50k of extra capital right now, I wouldn't purchase additional mining hardware. I would start trying to figure out where you think the bottom of btc is. Learn to trade on some level. No need to day trade. Dollar cost average in what you want to hold for the next few years. That's what I'm doing with my extra 15K. I also wouldn't be hell bent on selling in one year. Could be in for a disappointment, if this is loaned capital that you have to pay back in one year without interest.
I agree with this, now BTC my be in the bottum with trying to get bullish. It will make you get more profit and wait to buy the newer vesion of ASIC.
I don't have any ASIC's, but I wouldn't buy the S9. If you're going to buy a btc miner from shitmain, wait for the first batch of the next gen btc asic. Currently, they are just trying to offload a bunch of dog shit for as much as they can get for that dog shit.
I also don't believe that the 5800-6000 range was the bottom, so my 15K usd is in cash at the moment. Still mining away at the shitcoins that haven't been taken over by asic's and holding/trading for btc.