Depending on the state or province where you live, car dealers selling used cars will be required to disclose any police reports or damage claims on the vehicle you’re considering. A few organizations collect this information to assist consumers and dealers. In Canada, it’s CarProof and in the US it’s CarFax (to be merged as CarFax in late 2018). If you have the V.I.N. (that’s the serial number), you can buy these reports directly or simply ask the dealer to provide a complete CarProof/CarFax report on the vehicle being considered.
These firms use data provided by the insurance industry and law enforcement as well as car manufacturers and government licensing bodies to assemble a comprehensive history of the used car you want to buy. You will be able to see when the vehicle went on the road, where it was licensed, the number of owners, if it was reported stolen, damage claims made, and the size of the claims as well as its complete service record.
It is helpful to know where the vehicle was purchased as some states and provinces are very strict (and some very lax) on their reporting requirements. You want to be buying a vehicle that comes from a jurisdiction with very high reporting standards. Here in Ontario, Canada, we have among the strictest reporting standards in North America so cars from Ontario will normally command a higher price than those from neighbouring Quebec where the standards are more relaxed.
These reports do not tell everything but can be an important screening tool. If the dealer cannot or will not produce a full Vehicle History Report, you would be wise to move on to another dealer. This should be your minimum information requirement.