Dollar/Thrifty often have very good rates, but they also put an additional hold above and beyond the actual rental cost onto your credit card. While just about every company will authorize a hold for the rental rate or $200 - which ever is higher - Dollar and Thrifty tack on an additional $200-$350 authorization depending on the location, and perhaps, other factors. Avis/Budget don't do this unless you prepay for the rental, and then they'll tack an additional $100 hold onto your card. National/Alamo/Enterprise also don't tag your card with an extra hold. Those extra holds made by Dollar/Budget do not show in your rental car reservation quotes. You have to dig around the terms to find that you "may" have the additional hold put on your card at the time of rental, and you have to call the company to find out what the hold will be for a particular rental at a particular location. If you use a low limit credit card, or are close to your maximum on the card you plan to use for the rental, that undisclosed additional hold can ruin the start of your car rental.