Details from the terms of service:

Quote Originally Posted by AutoCheck
AutoCheck Vehicle History Reports ("Reports") purchased on the AutoCheck consumer site (www.autocheck.com), either directly or through affiliates, are intended for personal use only, and not for commercial use. "Commercial use" is defined as use by persons engaged in the business of buying and/or selling of automobiles, the resale or redistribution of the Reports, or any other business purpose. Without limiting the foregoing definition, personal use of the service is defined to not ordinarily exceed 100 reports during any 30-day period from the date of purchase or 50 reports in one AutoCheck session ("AutoCheck Session" is defined as usage of the AutoCheck.com site for a 30-minute period without refreshing or closing the Internet browser). Exceeding these limits will result in a temporary suspension of your account until Experian approves and reactivates your account at Experian's discretion. ANY COMMERCIAL USE OF THE AUTOCHECK VEHICLE HISTORY REPORTS PURCHASED ON THE AUTOCHECK CONSUMER SITE IS STRICTLY PROHIBITED AND ANY SUSPECTED COMMERCIAL USE WILL LEAD TO THE DEACTIVATION OF YOUR ACCOUNT, THE FORFEITURE OF THE RIGHT TO A REFUND OF ANY MONIES ALREADY PAID TO AUTOCHECK AND MAY RESULT IN LEGAL PROSECUTION. WE RESERVE THE RIGHT TO IMPOSE, AND YOU AGREE TO PAY TO EXPERIAN, AN ADDITIONAL CHARGE OF $19.99 FOR EACH AUTOCHECK VEHICLE HISTORY REPORT THAT EXPERIAN DEEMS WAS ACCESSED FOR COMMERCIAL PURPOSES. COMMERCIAL USERS OF THE AUTOCHECK CONSUMER SITE AND THEIR TRANSFEREES ARE NOT ELIGIBLE FOR AND WILL NOT BE COVERED BY AUTOCHECK BUYBACK PROTECTION.