5 of the Most Expensive Mistakes You Can Make Renting a Car

Image source: Upsplash/The Motley Fool

Despite political differences, I think Americans can agree on (at least) one thing: Renting a car is still not an easy experience. Whether it's waiting for hours to get help at the counter or combing through your contract for any hidden fees or clauses, car rental companies still make what seems like an easy credit card transaction (I give you money and proof of driver's license; you give me the keys) into an extremely unpleasant, confusing, and frightening nightmare.

In the midst of this confusion, most of us let our guards down and make mistakes with our car rentals that come back to haunt us. In my experience, the following five are some of the most expensive errors to avoid.

1. Buying rental car insurance

If you have personal car insurance and a credit card with rental car insurance as a perk, then buying rental car insurance is likely a waste of money.

Many of the best travel credit cards come with rental car damage waivers. This coverage basically relieves you of financial responsibility for damages to your rental car, including total losses, vandalism, theft, and environmental damages. It doesn't include liability coverage for you, your passengers, or other pedestrians. But it's crucial to have it if you don't want the rental car company charging you for damages sustained while the car was in your hands.

Likewise, your personal car insurance policy will likely cover damages and injuries you cause while driving a rental. If you're not sure if your car insurance provides this coverage, reread your policy before you pick up your rental. That way, when the company tries to sell you insurance, you can give a resolute no.

2. Not using your credit card's travel portal

Many credit card companies now have travel portals through which you can book rental cars. While these portals don't always have the best deals (see the next point), every now and then, they have a low price you won't find anywhere else.

What's more, your credit card may earn more points or miles when you use its travel portal. These extra earnings could make the portal the more economical choice when prices are roughly the same between it and a travel site. You might also get more value out of your points when you redeem them for a rental car -- though, on the flip side, you might get less value than for flights or hotels.

3. Using your credit card's travel portal

Contrary to the above point, credit card portals don't always offer the lowest prices for rental cars. Even with the extra points or miles, renting a car through a budget website might still have the best deal. Always compare prices before booking through the travel portal, as it could lead you to miss great deals for your dates and location on other sites.

Side note: Costco Travel also has great deals on rental cars. Compare its rental car prices with your favorite credit card travel portal to see which offers the lower rate.

4. Ignoring previous damages

Always -- always -- document any damages sustained to the rental by a previous driver. Even if the damage seems slight (like a little dent in the door), you don't want to be on the hook for paying it if the rental car company holds you responsible.

This happened to my colleague Lyle Daly. When he rented a car a few years ago, his wife noticed a stain on the seat. Lyle didn't document the stain, and the rental car company charged him $250. Although he ended up getting out of the charge, he admitted that he could have been more proactive in avoiding it in the first place.

5. Renting a car from an airport

Reserving rental cars at airports is convenient; you don't have to worry about taking public transit into the city or finding a way back to the airport when it comes time to drop the car off. But that convenience comes at a premium -- and it can greatly outweigh the extra effort in getting your rental in the city.

The higher price isn't just for convenience. Renting a car at an airport may also lead to extra fees and taxes. This is what can ultimately drive the price up, even if the per-day rate is roughly the same as nearby locations.

As an example, I recently looked at the cost of renting a car through Enterprise at both the Newark Liberty International Airport and Downtown Newark. The cost of renting the car at the airport was $330 for three days. This broke down to $215 for the car and $114 for taxes and fees. Meanwhile, renting the car in downtown Newark would cost about $254, which broke down to $222 for the car and $32 in fees.

Of course, it might be worth it to pay that $80 for convenience (even less if we factor in ride-hailing or transit to and from the Enterprise in Downtown Newark). But it's still not worth paying for rental car insurance if your credit card has it, or forfeiting extra points if that rental car is the same price through your favorite travel portal.

Keep these tips top of mind when renting your next car, and you can avoid these expensive mistakes.

We're firm believers in the Golden Rule, which is why editorial opinions are ours alone and have not been previously reviewed, approved, or endorsed by included advertisers. The Ascent does not cover all offers on the market. Editorial content from The Ascent is separate from The Motley Fool editorial content and is created by a different analyst team.The Motley Fool has positions in and recommends Costco Wholesale. The Motley Fool has a disclosure policy .