So roughly $750 for HD cards, a few hundred for mobo, case, power.  Not a lot of profit in if if not a scam.  This is a quick assumption of the GR1 (800MH/s).  Cheaper and more efficient to purchase the parts and skip the $100 shipping. 

This sounds a lot more like a group building rigs for mining based on current available hardware and accepting bitcoins.

Just my opinion.