Thanks for the tips Ellen. I found AutoSlash.com through Bottom Line Personal. I've used them for 3 rentals so far. On 2 of them my price was lowered 3 separate times after booking, and I ended up paying almost half of my originally booked price in the end. The other rental the savings were only about $10, but still lower than I found on other sites. Definitely my preferred car rental site from now on.