reprap doesn't print itself. it prints about half of itself. you still need to buy electronics, motors, and some metal parts, and fasteners at home depot. that being said, BotMill sells complete ones for 1500 dollars. or complete kits for 800.
i'm currently planning on having a friend cut out the lasercut mendel's parts for me on his CNC machine, and i already have the stuff you get from Home depot, and i'm planning on buying the rest online soon.
also, even once you build a reprap it takes considerable tuning to make it print properly.