I have purchased a used car 2 weeks ago from a dealership. And now i find out that the engine is covered in oil sludge badly and the mechanic says it will costs thousands of dollars to fix. Now when i look at the contracts i signed i realize they put the wrong vin number on the contracts. Basically I did not pay for the car on the contracts. Is that a valid enough reason to be able to return the car and get my money back?