Are you getting ready to hit the open road for an amazing travel adventure? Don't get stuck overpaying for your rental car, though. Hidden costs can really add up by the time you put the keys to ignite the engine of your rental vehicle. Of course, there are a few things you can do to make it so much easier for you to enjoy rolling down the windows and feeling the breeze in your hair. We at GET.com are more than happy to share with you these 4 simple ways to avoid getting overcharged for your rental car.

1. Don't Rent Near the Airport or Train Station

The first rule of being a savvy traveler is that you should never ever rent a car from an agency that's located in or near a major transportation hub. Rental agencies next to airports and train stations tend to charge much higher rates than agencies that are just a bit farther away.

This is because most people are willing to pay extra for the convenience that comes with picking up a car as soon as they arrive at their destination. Obviously, you can save money if you're willing to add a little extra work to your travel plans.

You should research to see if there are any rental agencies a few miles away from where you'll be arriving. Make plans to use a shuttle or taxi to get to an office that's not as busy if you want to rent a car for less.

2. Bring Your Own GPS

Most rental agencies aren't generous when it comes to lending GPS devices. Don't assume that a GPS will be included as a standard feature in the car you pick. You could be charged per day just to use one!

If possible, pack your own GPS along to use when you're on the road. Another option is to download a navigation app on your phone.

One other hidden cost to watch out for is the satellite radio. You will save a lot of money by simply downloading some music or podcasts onto your phone for you to enjoy while you're on the road.

3. Get a Smart Insurance Policy

Your insurance policy's coverage of rental cars may not seem like a big deal if you only go on a trip every few years. However, your coverage is a big deal if you travel regularly and use rental cars frequently.

Paying for temporary rental insurance every time you pick up a car can add up. What you want to do is sign up for a policy that will cover you whenever you drive a rental vehicle. You can also check with your credit card company to see if it offers a perk for keeping you covered when renting a vehicle (check out these credit card perks you never knew about).

4. Never Return Your Car Empty

Returning your rental car without a full tank is like throwing money in the trash. What most people don't realize is that many rental agencies will actually charge you for a full tank of gas regardless of the status of the tank when you drop it off.

Others will charge you much higher rates for the fuel they put back in the tank. Make sure your tank is full before you return your vehicle if you want to avoid paying an arm and a leg for some fuel.

Also, be sure to arm yourself with these 6 simple hacks to save big bucks on gas!