Summer travel season is already in full swing, which means the Groupon Coupons team is hard at work finding ways to help you save money on every part of your trip. We've teamed up with Avis and Budget Rental Car to drive down costs for car rentals at airports and everywhere else, too. Whether you're renting a minivan in Orlando or a convertible in Las Vegas, we've rounded up some rental discounts and other money-saving tips to help you get the best deal. Rental car demand is sure to be high all summer long, so be sure to book early, prepay, and join free rewards programs like Avis Preferred or Budget Fastbreak for extra rental perks you won't find anywhere else.