It is possible, but extremely difficult, to return a new vehicle once you have signed the contract AND driven it off the dealer lot. In some cases, dealers have a return policy, but the condition is usually if it turns out there was something wrong with the vehicle. If you're talking about backing out of a deal, however, it is not easy at all. A lot of people mistakenly believe there is a 3-day "cooling off" period, which is entirely false. Most states only allow this cooling off period only if the seller initiated the relationship that led to the sale. If you walk onto a dealer's lot, it is assumed that you intended to buy a car, and therefore, no cooling off period.