I agreed a part exchange value with a local garage for my wife's car. The deal was done and she collected her new pride and joy. The next day the garage called to say that they want a cash contribution towards the repairs required on our PX'd car before they can sell it on. Surely it's the garages responsibility to check out any car they are buying as part-exchange? I was unaware of the engine problems they claim it has which were apparently noticed very soon after we signed for the new car.