What exactly does certified pre-owned mean

You'd think that that's what it means. But not exactly. Certified when applied by a dealer to a used car, simply means that car model has less risks to the dealer and he puts a longer warranty on it. It's far more likely that you'll find a Toyota Camry under the Certified title than a Mini, Fiat, Kia, or Hyundai. But because these cars are more desirable, you'll also find that they have been better prepped for sale. Of course, you pay for that.