I had a user agree to buy a monitor from me - after seeing my advert which clearly stated what connectors it used and that there were some dead pixels. They private messaged me to arrange to buy the item - I then sent them a YouTube video which showed the steps and equipment needed to connect it to a modern laptop and I also sent them a photo of the screen in use taken they day before they were due to arrive with the location of the dead pixels clearly marked. The user arrived and I explained how to plug the cables in, and then tried to further explain regarding the need for extra hardware to connect to modern machines but was told that they knew all about that before I had chance to repeat the advice given by direct message. Despite agreeing to the price via direct message, the user then tried offering half the price, until I agreed to give him a discount as he had been at the door far too long, without a mask and I just wanted the sale over. He said that if it didn't work then he would be returning it. I stated clearly and firmly that I would not accept a return as I had just tested it, knew it to be working before that and that due to Covid 19 I do not accept any returns at all. As he stated that he didn't have change, and neither did I, he offered to pay the original amount, but I said that as we had agreed on a price, he could just drop the remaining amount through my letterbox the next day. This was not done and I then received a text saying that if he couldn't get it to work he would be returning it. I took the time to state that I had made it clear that I do not accept returns and that I had gone out of my way to explain the nature of the screen and the steps necessary to make it work on a modern laptop. A few hours later, I received a message stating that "If it doesn't work I will come and visit & smash it round your face". Naturally, I reported this to the Police right away. I wonder if anything can be done about such horrible experiences?