You could also build one. Here is a link to a website with the cheapest hardware all in one deal i know: http://gadgets3d.com/index.php?route=product/product&path=72&product_id=87 This is a starter set including 3 different endstops for Reprap, MakerBot or other printertypes. Than you only need the parts and the powersupply. The printing dimensions of a standard one is usually 200x200x200 mm, but if you make a MegaMendel it could be 400x400x400 mm I like building myself because you can make adjustment. If you do buy one pre-build, I advice not to buy printers with no heated-bed. Also heated-bed which are the printingsurface are known to bend after a couple of times. The problem is fixed by putting a glass plate over it. (The Orca has this problem) So you figuere that i'm not a fan of Kapton Tape Good luck.