10 Car Rental Hacks to Help You Score Upgrades and Cheap Rates

Assuming you tried these ingenious flight-booking hacks but still ended up dropping a ton on your ticket to Sioux City, you're gonna need to save cash on the rental car.

And to help you do that, we reached out to a handful of former rental car agents to get their top tips for scoring free upgrades, cheap rates, and the best cars.

Obviously, this is an easy one. Most people know by now that a lot of credit cards cover rental car insurance. Just make sure to read the fine print so you know exactly what's covered, and what isn’t.
 

If you don't really care what you drive, ask the agent if there are any cars he or she needs to get off the lot. Sure, you might end up driving a Geo Tracker (yeah, yeah, we know they don't make them anymore), but $10 a day is still a pretty sweet deal.

It sounds counterintuitive, but by reserving a car for Monday morning (a busy time when vehicles are being repaired from weekend accidents) or a Friday (or late in the afternoon on any day), you actually increase your chances of scoring a free upgrade. Quite simply, the more likely the agency's out of the cheaper cars everyone's trying to rent, the more likely you are to drive away in a luxury midsize.  
 

Rental car agencies are like hotels: their bottom line doesn't depend on how much they’re renting a car for as much as it does how many cars they can rent. So if you ask them to beat another agency's quote, there's a good chance they'll at least match it -- often, one or two agents told us, without even verifying the quote you're referencing.
 

Assuming that driving an even newer Kia Rio is important to you, airports usually have the most up-to-date fleet of cars. That's where they start before eventually being distributed to other branches.

Car rental agencies want to get rid of as many cars as possible, no matter the cost -- and agents usually have a good amount of room for negotiation. If you don't have a reservation but do have a few minutes to hit multiple rental car companies, find the one with the fullest parking lot, walk in, and negotiate.
 

If you’re flexible, you can typically get an upgrade for far less than the cost of booking the next class of car. The goal of the car rental agent is to get customers to spend more than their original reservation, even if it’s just a dollar or two. By asking whether they have any upgrades or specials when you arrive, more often than not you'll land a nice deal.

If the rental car company doesn't charge a fee for early returns, it can sometimes be cheaper to rent for longer (to get, say, a weekend or discount rate) but drop off before your rental period is up.

Yes, car rental agencies play hardball with their 24-hour rule but most do have a grace period, often up to two hours -- you just have to ask beforehand. They'll often give you more time at no extra cost.

Sure, you're technically breaking the law, and it's not that safe, but if you leave the car running while you slowly refill the tank, you'll be able to more accurately nail the level of gas you drove off with -- thus ensuring you don't hand the rental company extra money by overfilling.

Sophie-Claire Hoeller is Thrillist's associate travel editor, and is convinced she did something bad in a previous life that's cursed her to always fly within three rows of a screaming child. Follow her @Sohostyle.