My uncle taught me a number of things growing up: football, music, DJing, dancing, fashion, but the one thing he taught me was how NOT to sell a car.
My uncle loves cars and he would buy a car, do it up, use it for a bit, become bored of it and then flog it so he could buy another one that he would repeat the process with.
The problem was he thought that because he had customised the car to his own taste that this would make it worth more money, sometimes this will, but if you use the wrong kind of parts it will actually REDUCE the price of the vehicle.
I remember one time he bought a car from a guy in South London via a private ad, he negotiated a price and when we went to drive it away he realised that the car was an automatic and he had only ever driven manual cars before. He had to knock on the guy’s door and ask the guy how to drive it!
I will say one thing about my uncle though – he sure knows how to successfully negotiate cash for cars like a boss. Whether it be in London or New York he would always succeed in getting a good price when buying a car.