Recently sold a fridge. Only $50. It worked well for the 3-4 years we had it, but were doing reno's in the kitchen and a new fridge was part of the changes. Wasn't asking the world for it, just wanted it out of the house. Someone bought it, and came over in a van to pick it up. Even before the person physically took it out of our yard, I said to him that it will need to be transported standing up. If you lay fridges down, it effects the gas (or something like that) and the unit won't work properly. What did they do? They laid it down in the back of the van. I again said that you can't lay frdges down because they won't work properly. Still did nothing. Thanked us and drove off. I left positive feedback for being a quick payer. About two weeks later I received an email from the buyer to say that the fridge wasn't working. Said it would go for a few hours then would shut off, and when it was going, it would not cool down properly. I replied with "I told you NOT to lay it down, as it won't work properly". The buyer replied with, "I am a fridge technician, and I know how to transport a fridge". My (final) reply was, "If you're fridge technician, then you should know that you don't lay fridges down. Even the manufacturers and retail stores will tell you that. I sold you a perfectly good working unit. I can't help it if YOU did the wrong thing. The unit was working when you bought it, so it's out of my hands". In the end I noticed he gave me nagative feedback for selling a non-working unit. I guess it's true - you can't teach common sense.
