Thinking of buying a used car? You're not alone. In this slowing economy, people are looking to save cash whenever and wherever they can. But when you're looking for a bargain vehicle, you also want to make sure it's safe. Used car dealers know that and if you've dropped by a dealership lately, you may have been offered a free vehicle history report. In Canada, the most popular vehicle history report is called Carfax. For about $40, you can run unlimited checks on vehicles for a month. But if you rely solely on that report, you could be steered in the wrong direction. As Erica Johnson's report reveals, there can be big problems with Carfax. So when you're searching for the secret history of a used car, it's probably wise not to put all your trust in one vehicle history report.