Not Always. The Law Offers Some Aid for That Used LemonLemon laws protect new car buyers in every state in the nation, but it's far more common for used car buyers to get stuck with an unreliable vehicle, or to incur repair bills that cost more than the car. For such unfortunate consumers, it often goes downhill from there.

Owners of lemons, as these cars are often called, must still make car payments while their vehicle sits idle. One-sided arbitration clauses — built into practically every dealer's vehicle sales contract — work to keep many used car buyers from taking a case to court. Finally, a buyer may have to prove that the vehicle's problems existed prior to the sale in order to get some compensation. These factors plus the subject's complexity leave many American consumers in the lurch.

"Many of these cars are dangerous to drive," according to John Van Alst, used car fraud expert with the National Consumer Law Center. "Even if not, when a car becomes inoperable, it becomes a liability instead of an asset."

Although it's not always the case, some of these used lemons are sold fraudulently, such as when a dealer fails to disclose the vehicle's history, misrepresents the vehicle title or tampers with the odometer. Often, these dealers prey on the most vulnerable, low-income segment of the population.