My eldest son sold his PS4, it was only 6 months old although it wasn't getting used. I helped him this weekend perform a proper format, I also made a note of all the devices serial numbers (console and 2 controllers) We listed it locally and found a buyer almost immediately, guy came round was happy and paid cash. I was out last night when I got a call from my son telling me that the guy had just returned saying it doesn't work properly and that he wanted his money back. I asked him to inspect the device carefully and to find the serial number, I asked him to make a note of it and message me the information. He messaged me 5 mins later with a different number to which we sold! I told him to pass the phone to the guy and I told him that he shouldn't have just turned up without warning and that I have the money and he can bring it back tonight so I can deal with it to which he agreed. Now, beating the fudge out of the guy is not going to help although I'm not happy at all. Should I just make him aware that I'm onto him and that he should walk away or should I report him? He will no doubt try this on with someone else as he has a broken console he wants to exchange, that person may not be so lucky. What to do?