When the price looks too good
Before getting excited about a low price, compare the unit against at least three similar listings in brand, model, year, and mileage. If the price sits notably below average, there's a reason — and it's rarely good luck on the seller's part.
The most common explanations: a hidden mechanical problem that would cost more to fix than the discount offered, an outstanding lien or debt on the vehicle, or — the more serious scenario — the unit has an illicit origin and the seller needs to offload it fast.
A fair price backed by clean paperwork is always a better deal than a low price with unanswered questions.