I agree with everyone else one this one, dont buy it! A quad with 500 miles should look and start just like a new one. And the rust, this could possibly be where the welds or the metal itself is stressed and cracked from the accident(accidents?)

 

Derek,

Are you saying the motor has 500 miles on it & it has already been rebuilt? If so my question is what happened to the motor! You should get more than 500 miles before having to rebuild.

Befor purchasing take it to a mechanic & have him check it out its worth the $50 or so investment to find out whether or not something is wrong.

Goog luck.