"What you see is what you get," that's what many rental car companies promise, but the rate you see advertised is often inflated with hidden surcharges you wouldn't think to look for. In the end, you may be paying more than double the "base rate". 

Look for previous damages

In most cases, you are not the first person to drive your rental car. It has a whole history before you took the seat behind the wheel and that history could include damages big and small. In order to avoid paying for damages incurred by previous renters, inspect the car before leaving the lot. Don't end your inspection after simply taking a quick walk around the car. Check for small scratches, loose parts, and leaks. Even make sure the windows work properly. Never assume that a ding is too small or that the company already knows about the damages. If it doesn't appear on the car condition form, inform the rental company.

Age

Most people assume that you have to be at least 25 years old to rent a car. However, in the U.S. you can rent a car as young as 21, but you will incur a fee. If you're under 25 years old, you can expect to pay a renter's fee between $25 and $30 per day. The penalty for aging doesn't stop there! Internationally, you can be charge for being over a certain age.  Those over 70 years of age can be charge a fee to rent and even be denied a car entirely. 

Additional drivers

Taking long trips in the car by yourself can be daunting, but you might want to think twice about including a friend as an additional driver the next time you rent a car. Adding more than one driver to your rental agreement often carries a surcharge. Fortunately, some companies, allow the renter's spouse or domestic partner to drive with no extra charge.

Frequent-flyers

Using your car rental to earn airline miles sounds like a great idea. However, adding a frequent flier program to your rental is a gamble. In most cases it will not affect the price, but some franchises charge more for using frequent flier programs. You can expect a fee around 1.2  cents a mile. Double check with your rental company to find out if the points you gain are worth the fee you may incur. 

Airport surcharges

Location, location, location! Renting from an airport often means a hefty airport surcharge (concession recovery fees, customer facility charges, etc.), which can total 10 percent or more of your total price. Consider taking a shuttle to your hotel or an area away from the airport (possibly downtown) to rent a car. You might even be fortunate enough to book with a company whose off-airport rental offices provide transportation to and from the airport.

Gas

With the ever-changing cost of gas, it might sound tempting to let the rental agency fill up the tank for a set price. Unfortunately, while they might advertise a discount up to 10% off a gallon, you may still be paying more than if you filled up the tank yourself. With the prepay option you are offered a lower price per gallon, but will be charged a full tank whether you used all the gas or not. There is no refund for unused fuel.

If you want to play it safe, fill up the tank yourself. The gas stations closest to the rental location will have the highest prices, so try to find a gas station a few miles from the drop off location. Either way make sure you put gas in the tank before drop off because you will often pay a high premium for returning a car with an empty tank. Also, some rental companies require a receipt for the fill up that’s within 10 miles or so of the airport, so be sure to save the receipt so that you are not charged when you drop your car off.

Drop off time

You'll find that the strictest rule a car rental company has is the drop off time. You can't be too late or even too early without being charged. When you look at the fine print you'll realize that it's a maze you have to navigate through. If you come in too late (over the 30-minute grace period) you will be charged a full extra day. Hand it in early and you may have an early return fee or worse, your rate structure might change. A rate change nightmare could be signing an agreement for the week and then handing the car in so early that your weekly discount is voided and you must pay the daily rate (which can add a couple hundred to the bill). 

It's not only important to be mindful about when you drop your rental off, but about where you drop off too. If you are planning on a one-way car rental, you're sure to incur charges. If this charge is not specified, it is likely incorporated into the base rate, making the base rate higher than it would have been for a rental that picks up and drops off in the same location.

Always check with the agency to find out their exact policy on late returns and one-way rentals before booking.

Mileage caps

Most rental companies offer unlimited miles for the car rental period, but some smaller, local companies will add on extra fees for surpassing a daily mileage maximum. Also, be cautious of "special" rates, some may not include unlimited mileage, so it's smart to read the agreement thoroughly. When choosing between a rental with unlimited miles and a cheaper rental with a mileage cap, you might find a bigger savings with the former.

And if you plan on taking an extra-long trip, be aware that, depending on the agency, there may be additional fees and/or you'll need special insurance in order to cross state lines or national boundaries. 

Extra / accessories

How often have you've gotten in the car and realized you've forgotten something? If it happens at a rental company, they've got you covered, but it will come at a price. Car rental companies charge extra for accessories like a GPS, child car seats, roof racks, etc. These extras could cost you $5 to $25 or more per day, so it'd be wise to bring your own car seat (which many airlines allow you to use on the plane for free) or even print out directions beforehand.

Vehicle licensing fee

Most states allow car rental companies to charge extra to recover the costs of their vehicle permits and taxes. A vehicle licensing fee, sometimes known simply as VLF or Road Tax, can add about $5 to your daily rate. This is another one of those cost that you may not be told about in advance and could be included in the total rate.

Insurance

The biggest (not so) hidden fee and hard sell you'll find at car rental agencies, is insurance. It makes sense to want to cover you and the vehicle in case of an accident, but there are other options outside of the rental company's Collision Damage or Loss Damage Waiver (CDW or LDW). 

A CDW is nice because, just for an extra $10 - $30 a day you can avoid liability for any damage to the vehicle. That's right, with a CDW if you damage a car, you can return it and walk away with no further responsibility. However, that can be costly when compared to your other options.

Instead of opting for the rental company's liability coverage, you could use your personal insurance or your credit card. Your own auto insurance policy may cover collision damage and personal liability for temporary use of a rental car. This method does risk affecting the rates on your existing car insurance policy if you get in an accident in a rental car. Your credit card (if used to book and pay for the rental car) may provide secondary collision coverage.

And if you're a frequent car renter, another option is to purchase a non-owner auto liability insurance policy from an insurance company for about $300 a year. Whatever you choose, remember insurance is optional in most U.S. states (though sometimes it is compulsory and built into the base rate).

Taxes

Along with these hidden fees, you will have to pay the taxes that come with it. You could pay more than 30% in taxes on top of the rental car hidden fees ... and these state and local sales taxes are unavoidable. In many countries it's common to have a law that adds taxes to rental-car prices in order to pay for things, such as stadiums. The car-rental companies just tack the required fee right onto the bill, and there’s no way to get out of it.

An agreement that saves

If you are looking for a transparent and hassle free way to rent a car, you should consider the CoVest / Hertz agreement. Hertz Corporation has partnered with CoVest to bring our members better travel options. Operating their vehicle rental brands in corporate and licensee locations throughout 150 countries, the Hertz Corporation is one of the largest worldwide airport general use vehicle rental companies. 

Why Hertz?  Product and service initiatives such as Hertz Gold Plus Rewards, eReturn, Mobile Wi-Fi and their newly improved car fleet set Hertz apart from the competition. Additionally, CoVest members using the Hertz agreement gain access to exclusive benefits including no blackout dates, no energy surcharges, aggressive pricing and customer specific reporting.

Visit www.covest.com to view the CoVest / Hertz deal structure.