Carfax is indispensable tool for people buying used cars. I had to look for over 150 cars to buy one for me. There is a lot of fraud in used cars and Carfax helps to fox those dishonest people. It also helped in judging the good price for a car based upon the maintenance history. The maintenance patterns and the mileage histories are essential to gauge a used car. In the end, I would say if you are buying any used car, please get a carfax. Its only $55.0 unlimited account (license plates with 5 VINs) that would save you around $5-10 K. I hope that Carfax would extend unlimited $55.0 account for VINs also.