CARFAX is a company that provides reports for the history of used vehicles. A CARFAX report will tell you important facts about a used automobile, such as previous accidents, past repairs and the number previous owners. Sometimes a CARFAX report can cost money, but you can get CARFAX reports for free in several ways.
Use CARFAX's free service to find cars for sale (see link in Resources section). All of the cars listed for sale on the CARFAX website include free CARFAX reports.
Search the websites AutoTraders and Cars for used cars. Both of these sites offer free CARFAX reports (see links in Resources section). Just look for the "free CARFAX Report" links.
Check the dealer's website. If you plan to buy a car from a dealership, check its site for free CARFAX reports. Many dealerships now offer this service on their websites.
Ask private sellers to purchase the CARFAX report. If they have confidence in the vehicle they are selling, they will usually oblige.