CarFax
The industry standard, most common report. This should be a go to for all vehicle purchasing decisions.
$7.99AutoCheck
AutoCheck reports are similar to CarFax, but will occassionally have more detailed collision records.
$7.99Manheim Auction
If the VIN has run through a Manheim auction lane, you're going to want to know what's in the this report. Great for seeing the condition a dealer purchased the car in.
$9.99