Carfax allows me to check the history of a car before purchase. I have used the service for years to help me get a good used car. I recently wanted to purchase a 2000 Special Edition Mazda Miata. I was able to find a low-mileage 2-owner cream puff just 140 miles away. By pulling the Carfax, I was ready to make an offer when I first saw the car. In fact, I had taken a certified check with me for the amount of my offer and I bought the car on the spot! Years ago I bought a certified used car from a local dealer. Did not "bother" with a Carfax. When I got ready to sell the car 6 years later, I found out that the car had been wrecked prior to my buying it from the dealer - that hurt my resale value. So, I no longer skip the Carfax!