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.