Autoslash is a website that finds a low car rental rate for you, and/or tracks the rate of a rental you have already booked. I use Autoslash every time we need a car rental. Usually I will start with Autoslash to find a good rate for our trip, and then book using the suggestions they provide in an email a little while later. Once you’ve booked your car, you can enter the details into Autoslash’s tracker, and they will alert you if they find a better deal. I have rebooked cars many times, and saved lots of money using this free service. Give it a try the next time you need to book a car rental!