Sam paid for his auto rental in advance before leaving for Europe. He got an excellent dollar-guaranteed rate and avoided the three-percent foreign transaction charge that his credit card would have imposed had he waited to pay in Europe. When he finished the rental, however, the rental company handed him a bill for the local road/registration tax, a fee of about 10 euros. Since Sam was returning to the U.S. and wanted to get rid of his euros, he paid in cash. Big mistake. You see, there was also minor damage to the car, which the rental car company routinely billed to his credit card a few days later. When the rental company sent Sam the bill in the U.S., he turned to his credit card for reimbursement under their free CDW coverage. In order to be eligible for credit card insurance, however, the renter must pay the entire cost of the rental with the credit card. Since Sam had paid for an item (the road tax) on the car rental invoice in cash, there could be no reimbursement. He had to pay for the damage himself. Fortunately, the car was only scratched and the repair bill was about $630. Had it been totaled or stolen, Sam would have been on the hook for its full value.