Not everyone that goes to school is 21. I'm 34. I'm getting my Master's at the university I work at plus my GI Bill so I'm actually getting paid to go instead of paying. Plus,  I'm an adult with a full time job and a credit card.

It's $7k OBO because you wouldn't believe the low ball offers people give. If you think it's too high, make an offer. Sure you can build your own, if you want to spend the time building and tweaking to get the best hash rate. Took me about a month to get it just right but maybe you have more time than I do. Also, you couldn't even get the cards for $3k-$4k, let alone all the other hardware.