I think you can sign up for a 30 day account, and run ONE report, and then cancel your account for a full refund (at least this used to be their policy).
Sneaky... yes. Why do I suggest doing this?
Well, I had a problem with the CarFax people... and THEY started it.
When I was in the process of buying my last vehicle, I bought one of their "unlimited" 30 day subscription accounts. I was interested in a truck on a local dealer's lot (who has since gone out of business), but I just had a gut feeling about their inventory. Something just didn't feel right about this dealer.
I ran a CarFax on a small portion of the vehicles in their inventory, and my gut feeling was confirmed. The vehicles in their inventory had some of the most interesting histories. Nothing was illegal, but most were interesting. It was a mix of ex-rentals, ex-leases, vehicles that had been auctioned off several time in several states (which can suggest a tactic known as 'title laundering'), vehicles from hurricane flooded areas, vehicles with a history of repossession, vehicles with several owners in a short amount of time... just about everything except vehicles that had a history of being from one local owner.
I also ran reports on a few other trucks as well, at a couple other dealer, and a few off of eBay.
A few days later, I received an email from CarFax accusing me of being a dealer (without any proof of such accusation), and that they were cancelling my account without a refund.
I simply asked them to prove that I was a dealer, or was otherwise violating their terms of service, and (*surprise*) they couldn't do it. They had no proof of anything.
After a few more email exchanges over a day or so, my account was finally restored for the remainder of my 30 days, but I was told in a not so polite way to take my future business elsewhere.... when I was guilty of doing nothing wrong.