We bought a used car from a dealer that we hated it within 2 weeks, they would not unwind the deal (buyers remorse), even before 3 days were up. Their game was bring it in repeatedly so the mechanics could go over it and fix the complaint, The problem was the backseat passengers were treated to a virtual ride in a cement mixer but with outdoor scenery. The front seat ride was a bit better, but not much.
The second regret was buying a car from a private sale, should have spent the money on bringing our own mechanic. The seller claimed he was a mechanic himself and there were no problems, yeah right. Paid $1,500 for the car and $1,800 in repairs.