Went to rent a car for a month-long work trip in Tempe. The price I was quoted at the counter for the economy-sized car was more than double the price on the Avis website. When I asked why there was such a large price discrepancy, the person at the counter said I must have misinterpreted the per week price as the per month price. So, I assumed the rep at the counter was correct and I had been mistaken, and went ahead and rented the car.
When I got to my hotel I looked up the car again, and the price for the whole month was indeed what I'd thought it was---I hadn't "misinterpreted" anything. I e-mailed Avis customer service and they said the price difference was due to a "self-service discount" for booking online. A discount of 50%, really? I then looked up economy-sized cars with Enterprise, booked one online for approximately the same price as Avis' online quote, and then took the other car back to Avis the next day. The person in the return area asked why I was bringing it back early and I told her exactly why. Her excuse for the large price difference was the cost of the insurance--which I had specifically declined.
I have always used Avis as they are typically cheaper than the competitors and have had good experiences with them before, but this experience may have turned me to Enterprise as I had a much better experience with them in Tempe.