I've had a few deals like that, often where something was "broken," but the seller didn't really know how to use it ("Studio shutter fires at only one speed"--well, yeah), or it was a routine fix that people are afraid to touch. It is rare that some really old LF shutter is really in good working order, for instance. Better just to factor in the cost of a CLA and consider it a bonus if it turns out to be unnecessary.

Knowledge is worth money.