I would seriously consider holding on to that money for now and be ready to buy up the coin(s) you intended to mine directly in the next few months. The rig you are contemplating will probably cost you well over $3,000 right now due to the highly inflated GPU prices. The coin mining difficulty levels are all at all time highs and showing no signs of slowing down, meanwhile most coin prices are continuing to go lower, also with no signs of reversing any time soon.

Using ETH as one example, I expect it to retest the $500-$600 range within the next month or two, and possibly even go much lower. Even using the $500 figure as a low you could instead buy 6 ETH directly and hold with that money. A 5x 1070 rig will currently mine 0.0117 ETH per day, meaning it would take you 512 days of mining to earn those same 6 ETH coins. This of course assumes that difficulty does not rise anymore which we all know will not be the case. Also, this does not factor in the electricity required to mine those 6 ETH over that time period, so you would likely be looking at a much, much longer payback period probably on the order of 800+ days.