Surely the seller can then fight the fact that something was stolen?
They are going to valuate the car when it gets to their warehouse. If they come up with a stupid value of like 100k, then surely it was reckless lending on their part? The car is in better condition now than when it was bought as some dents were taken out.
True. Unfortunately, 99% of the time, the person who surrendered the vehicle does not attend the auction and inspect the vehicle before it goes on the floor. If this is done, you can demand a stop to the auction and demand that the bank repair the vehicle to the condition it was before the auction starts again for the vehicle.
Also, it is imperative that you photograph the condition of your vehicle, inside and out, before handing it to the bank. Do this, even if it takes you 2 hours to do. They will wait for you.
If you claim any problems to the vehicle, the bank will ask you to provide evidence of the condition of the vehicle before it was surrendered.
Edit - I also need to mention that when you surrender a vehicle, often the bank will wash and clean it up. In certain instances they will repair small damage before it goes on auction to attempt to get more for the vehicle on auction.