I have had plenty of experience grading and then negotiating for vehicles to purchase. Since CARFAX has been around I have used them on a regular basis. My experience with CARFAX has always ended with checking for unseen problems which has been a real relief for me because you can get caught up in deal making and forget doing the proper research. This is the reason I will always use CARFAX in the future to identify problems I would have never been able to see when negotiating. I give CARFAX a five star score rating and thank them for their help to avoid making a bad car deal and ending up having to fix a flawed vehicle which I would have lost money on.