Now, if, for example, you buy a car that is advertised as runs & drives and it turns out the car does not, in fact, drive - you can talk to them and have them buy the car back or whatever. This happens every now and then. But aside from that, you’re SOL.
I’ve purchased a number of cars from them, and one issue that comes up fairly often is that they load the cars via forklift. Often, the forklift will cause damage to the underbody that was not present previously. In cases like that, you’re still pretty much SOL.