How do you sell cars in test drive unlimited 2

You can't. It's not possible to sell a car just like that, don't ask me why, I'm just as annoyed as everyone else. The only way to sell a car is if you don't have enough money to buy another car, which will give you the option of selling one of your cars to be able to afford the new one. This is of course as stupid as it gets, as you end up with the same amount of money (perhaps a bit more depending on which car you sell) as you had before. Hoping Eden Games will fix this in an upcoming update, but I strongly doubt it...