use it once and you're going to want to use it a lot more!
Very satisfying to watch and listen to. With so many gears and chains and sprockets cams and cranks and wheels and slides.... amazing that they EVER worked, let alone 50 years later.
hard to tell you what to look for because there's so much going on.
Best if you can try it out before buying - meaning at least to cycle it. The main components should be obvious - if everything's turning and the lift's lifting and nothing's making horrible noises, there's a good chance it'll work for you.
Just be damn careful near the thing.
A friend of mine lost both his arms and half his face in one of them.