It is a big negative...get a mechanic to check it out
I bought one once for my wife. Just make sure the remainder of the factory warranty is transferable. That is the only problem I had. The local dealer wouldn't honor the warranty. (bought car direct from rental company) The GM zone rep convinced him otherwise. Turned out to be a pretty good car. Rental companies have good PM programs. If it is a cerified used car and the dealer will stand behind it, and the factory warranty is good you should have a problem