Doesn't sounds shady just sounds like a change in heart. You drive the car the first week and instead of signing it all over get rid of it. I would be more so wanting to buy it if its through the dealership but I'm sure they will not offer any type of warranty, but then again they might since they're taking a chance to buy it hoping you will buy it from the dealership. I would have the techs at the dealership check it out or take it down the road and have it looked at. That's if it's worth all that hassle.