If you rely on CARFAX to be 100% you are smoking something. Is it a good tool to have sure. Not everything is going to be reported. Also things that happen that people never claim for insurance or where a ticket was never given will show will not show up. Is it worth the 40 bucks to have that info, maybe maybe not. Think I have done 3-4 of them in the past. 1-2 of them seemed to be pretty complete, the other ones just showed when the car was bought and that was pretty much it.