Depends on what's wrong with the original contract. I've never attempted to pull this "scam" but I have definitely had to bring people in to re-sign before. In most cases, what you say about the person being able to keep the car isn't true. Sometimes it's because they didn't get financed with the terms we hoped to get them financing for. The contracts are specifically written contingent on the financing getting bought by a bank. This was rare, but it did happen. In these cases, the person had only a few options: come up with the financing themselves, come up with cash, re-sign a new contract with new terms or give the car back. More commonly (still rare), people would have to come in and re-sign because the VIN was wrong on their contract (part of the F&I manager's job is to check the VIN on the car against the VIN on the contract, but sometimes things get missed). In this case, the person does not own the car that they're driving. They have to bring it back. A google search for Glock kaboom gives 100k+ hits.. how "common" do you think those are? I'm telling you, as a guy who made a living selling cars and running a car dealership for several years, what I saw and experienced. You can choose to believe me or not, that's up to you, but I think it's fairly obvious that I'm probably a better source of information than a google search. Google searches will not give you an accurate picture of how frequently bad things happen due to selection bias.