<font face="Verdana, Arial, Helvetica, sans-serif" size="2"> ... I received a letter from a car rental company. They told me that they ... forgot to bill me one rental more than a year ago (15 months!!!).</font>
A long time ago I read an article about a company that specializes in going over rental receipts for car rental agencies. The number of mistakes in the customers' favor was so high it was worth it to to rental agencies to hire them - something like 40 percent of all rentals are mischarged. The company worked for something like 50 percent of the amount of money they recovered.