It's best to stick to a credit card for car rentals, but in the few instances where you want to put it on a debit card, there are a few things to keep in mind.
Some airport locations may require a return flight when renting a car with a debit card. The best fix for this is to buy an airplane ticket on the spot and then immediately cancel the flight once the flight is refunded. Every U.S. airline offers a 24-hour penalty-fee refund policy.
In this particular example, our staff found a weekly car rental from Long Beach Airport for $142.54, almost $100 cheaper than it was everywhere else within 20 or so miles. However, in order to rent the darn sedan, a return flight departing either from LGB or LAX was needed.
This was quickly solved: Standing at the Hertz Gold Plus Rewards line, we quickly searched for a flight departing LAX on the same day we'd return the car and bought a quick flight to San Francisco (SF0) for $51.20.
The timeline looked like this:
10:20 AM Arrive at Long Beach Airport (LGB)
10:26 AM Go to Hertz Gold Plus Rewards line.
10:27 AM Purchase plane ticket from LAX to SFO.
10:29 AM Receive keys to car.
10:31 AM Enter car. Cancel ticket. Receive refund.
Not more than four minutes passed between the minute we bought the flight and the moment we cancelled the ticket.
Truthfully, most car rental agents are unlikely to ask for the confirmation number or to see the ticket as long as a flight number is give. But in case.
Credit cards are almost universally accepted for car rentals because agencies are assured of the creditworthiness of the individual renting the $35,000 car. In this regard, debit cards raise a red flag and paying in cash is not even a thing. I think. Has anyone tried the latter?