Now that Memorial Day has passed, it's officially road trip season here in the U.S. And for many travelers, that means negotiating the ins and outs of the rental car contract.

My rental car routine has stayed the same for years, and it has saved me some money: I book my car with a blind site such as Hotwire (, decline extra insurance offers, and make sure that I drop the car off at the same airport where I pick it up. Normally, I also fill up my own gas tank before return, usually at a station away from the airport so the price isn't marked up too much.

But on my recent trip to Napa Valley, I realized that the gas rate offered by Hertz ( was nearly 25 cents lower per gallon than the average price at the pump in California. Knowing that I would use the entire tank before returning the car, I bought their gas and saved some cash -- proof that even the trustiest travel routine is worth revisiting sometimes.

With that in mind, I solicited ways that other people save money on rental cars -- and discovered some new tricks that I'll try next time I hit the road. The tips below are mostly for domestic car rentals; I'll outline international car rental tips in a future story.

Research gas costs. How did I know what the average gas costs in Napa were? I downloaded GasBuddy (, a free iPhone app that shows you what gas prices are in a certain area. You can also use the app on the road to find the closest gas station with the cheapest prices. Similar apps include AAA's TripTik Mobile and GasBook.

Be fee-conscious.
As with airlines, rental car companies have raised their revenue by imposing fees -- some of which are completely unnecessary as frequent traveler Susan Kohlback found at the Miami airport.

A rental car agent insisted that Kohlback add a toll transponder to her agreement because, the rep claimed, she'd be going through a tollgate outside the airport that wouldn't accept cash. Knowing that she wouldn't be using the Florida Turnpike, Kohlback declined the transponder and its extra cost -- and found that she could pay cash on the highways she needed.

"There was no reason for us to pay a daily fee," said Kohlback, editor of the website Wicked Good Travel Tips (

Rent off-site. Other fees that creep into your rental agreement may have nothing to do with the company. At Phoenix Sky Harbor, for example, you'll pay a daily customer facility charge, concession fees and a 3.25% county stadium tax, in addition to other state taxes.

You can avoid some of these charges by taking a cab or bus to an off-airport rental company; Enterprise ( is one company that has many neighborhood rentals, for example. But do check the hours first, as many off-site rental car companies close at business hours during the week or shutter completely on weekends.

Inspect for damages. Often travelers are in such a rush to leave the airport that they forget to make sure the car is dent and scratch-free. "My new habit is to turn on the video recorder on my phone and make one quick walk around the car," said Ben Schorr, CEO of Roland Schorr IT consulting. "It takes less than 60 seconds and it's a good way to protect myself against false claims later."

Join loyalty programs. Even in these days of travel deal aggregators and coupon websites, it still pays to join a car rental loyalty plan -- especially if it's free. Besides allowing you to bypass long lines, members often get free upgrades and more. "It's helped us get an SUV or minivan in a pinch for the cost of a compact," said Marshall Stevenson of Hi Hawai (, who belongs to all the major loyalty programs. "Now that's savings!

Travel journalist Chris Gray Faust dishes up travel tips on her award-winning blog, Chris Around The World. Join her on Facebook, follow her on Twitter. or leave a comment below.