You've got to prepare yourself for this. Think of it as a school exam. Think of all the questions that could be asked and prepare yourself for the answers. After a couple of car flips, this will be natural but be the best actor you can on your first few flips and bluff your way through. Practicing your answers in front of a mirror will give you confidence. But answers to "How long have you owned it for?" Can only be truthful - so, for example, two weeks. That'll naturally spring the next question ( that you asked) as alarm bells have already rung in the buyers head, "So why are you selling." Well that can be an assortment of reasons. For example. Depending on your age. "Your sister, son, daughter, niece, cousin has just been accepted into .....College, and although I love this new car, I feel like I'd like to surprise them and help them with some expenses." That'll earn you a nice warm pat on the back from the buyer. So best to wiggle your way out like that with an answer that not only satisfies them but also endears you to them as well. You'll earn a bit of trust straight away.