I haven't bought anything from KEH in over a decade, but at the time I bought an "ugly" Xenon in LTM.
The front lens coating was badly scratched, so I removed it completely . And it required tightening of a loose set screw somewhere internally.
Resulting images are okay, for a Xenon.
I also once bought a Leica I off them that was supposedly "Inoperable". I never figured out what was supposed to be wrong with it, because it worked fine.
As I recall KEH had a no-questions-asked return policy at the time. Don't know if they still do. So you could always take a chance.