More than once I thought I had a good deal and was surprised to get email from AutoSlash telling me my rate had been reduced. In addition to offering a consolidated list of options for rentals, AutoSlash will track not only rentals which are booked through their links, but also those booked directly from rental agencies. (The only problem I ever had was when booking through a credit card site, that did not send me the actual booking number at the agency... and I later found that I was NOT getting the best rate!). Use this! It's good!