Transcript for Nationwide consumer warning for car renters

Liberty Mutual Insurance Next tonight, a nationwide consumer warning. Payless car rentals under fire over its fees. Hundreds of customers complaining they were charged for services they did not want. What happened when our cameras went undercover. Here's ABC's gio Benitez. Hello. Reporter: ABC news undercover, renting cars from Payless car rental. We take each car to our expert mechanic for inspection. This is a dangerous tire. Reporter: Payless towed the car. The manager apologizing, giving a full refund. That car shouldn't have even gone out. Reporter: Payless also facing questions about fees. A proposed class action lawsuit, customers claiming they were charged for services they didn't want. Plaintiff Richard Alexander says the online quote for his Payless rental -- $217. He says Payless told him he was getting a free upgrade, but when he returned the car, he was shocked. The total? $528 after charges for insurance and added services, not the $217. I believe he was told two or three times I do not need this. Reporter: After receiving more than 800 complaints on fees in the last three years, the better business bureau giving Payless the worst possible rating. An F rating. An F rating. So they have sales practice issues and contract issues and billing issues with consumers. Reporter: Payless declined our repeated interview requests in a statement saying, "The tire problem you described is highly unusual. Safety is a top priority and we have followed up with the supervisor at that location." As for the lawsuit, Payless said they can't comment on pending litigation. David, tonight, the better business bureau issuing a nationwide warning about what it calls a pattern of complaints about Payless sales practices. David? Gio Benitez tonight, thank you, gio.

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