A history report collects what official records know about a car. It cannot tell you everything, but it tells you where to look.
Title
A clean title is what you want. Salvage, rebuilt or flood titles mean the car was written off at some point and is worth much less.
Owners and use
Many owners in a short time, or a past as a rental or fleet car, are not deal-breakers, but they explain wear and should lower the price.
Accidents
Reported damage is rated by severity. Ask for repair invoices and check that panel gaps and paint match on the side that was hit.
Service gaps
Long gaps without a service or a mileage record can hide a rolled-back odometer. Match the service book with the report line by line.

On “Reading a vehicle history report”.
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