The first choice is to rent a car from an off-terminal company.  They usually have lower rates because they do not pay for the in-terminal space.  The drawback from these companies is that your party must take a shuttle to the car location which means undertaking the cumbersome task of moving all of your travellers and their luggage on and off a shuttle, waiting while the driver rents the car, and then repeating the process on the trip home.  This takes extra time and effort and can be a hassle to your travel experience.

The second choice is to rent from an in-terminal company.  As far as Orlando International, once the paperwork is taken care of, your party takes the luggage across the street to pick up the car.  It is quite easy and there are limited delays.

Now for the savings tips regardless of the company.  Car rental companies generally cannot charge your credit card until you actually rent the car.  I have gone to a general website such as Orbitz to view the car choices and prices for the dates needed. Once you see a car and price of your liking, go directly to the company websites. Consider that some of lesser known companies such as L&M  as they offer good deals and are reputable. You can then view the prices and availability and make a choice.  Now make the reservation and keep the reservation number handy.  Rental rates often change. Every week or so go back and review the rates. Check the rate of the exact car type and dates needed.  If the price is lower, use your reservation number and modify the existing reservation for the same  at the lower rate.  I have done this as many as 5 times and have been able to reduce my price by over $200.

Another tip is with insurance.  Many people in the US have auto insurance which covers you in a rental car.  If you have proof of insurance with you and you are in an accident, there is usually no issue.  The car rental companies will want to be paid for damages but you have to file a claim with your insurance company.  The car rental companies may pressure you to buy insurance and the only benefit (with cost) is that your liability is reduced.  (this is what they tell you) So, if you want this peace of mind, pay the extra cash.  It adds up.

The last tip is about car rental choice.  I have reserved the economy car many times.  The companies are limited to how many cars they have in that class and will ask you if you want to upgrade the car type at additional cost.  I refuse to pay more for the upgrades.  More often then not, they are out of the economy models and they will act as if they are giving you an upgrade for free.  So what, I have gotten models far above the economy model and yet paid the economy price.  Car rental companies make money on the extras such as insurance and upgrades that are on the spot offerings at the rental office.  Be prepared ahead of time and stick to your guns.  In the long run, you will get more for your money.