AutoSlash saved me about $400 when I recently needed a rental during a family trip. It was so simple, I reserved a car (at a shockingly high price), entered the information at AutoSlash and had a lower rate within 30 minutes. I rebooked at the lower rate, and a few weeks later AutoSlash found an even lower rate. By the time I picked up the car, I ended up paying a bit more than half of the original rate. Highly recommend!