Bought a laptop for $25 at a thift store. Was a bit of a gamble because the case was completely open and case screws and ps were missing. But it looked great. Turns out some screws and a universal ps is all it needed.
But don't buy laptops like this, ASUS X551M. You have to open the case to replace the battery, harddrive, wifi, ram, optical drive, and EVERYTHING.
Horrible(ok for $25) especially since this isn't an ultrabook. DON'T support them by buying when components aren't accessible!