BTW this is not meant to take away from the OP generosity.
I agree but at least if it does show accident/rebuilt title etc the it will have at least saved you the time and effort to go look at the car. Definitely get your car checked out by a mechanic as well and don't rely on this.
Clean Carfax report can give you a false sense of security. They show a couple of cars with a clean report that been in an accident.
It can take months and in some cases years for Carfax to receive reports about a car. And other times they may never receive it.
Carfax's spokesman in this show, kept repeating that Carfax relies on other sources (insurance companies, police etc.) to send updates to them. Never ones did he say that Carfax makes an effort to go out and actually look and collect such information (ie., being proactive).
Take it to your mechanic even with a clean Carfax report. The Carfax spokesman at the end of this short 2 minutes video (link above) says people should take a car to their mechanic, regardless if it is a clean report or not.