I make the assumption that "as is" and "untested" mean "broken." Most of the time it's absurd that no one would test the things that they list that way. One guy was selling a video projector that he bought at a local church auction but, of course, didn't test it. He bought a huge projector, brought it home, and didn't bother to hook a VCR up to it. I know that some people honestly don't test the things that they buy or don't know how (especially if it's a large pawn shop, etc).
But, it's definitely a Buyer Beware situation.