When are you renting? $600 sounds incredibly high. I usually find Orlando to be some of the cheapest rentals anywhere. They have such a high turnover, and such low costs, and such competition that they have to keep prices low.
Be careful that you are renting from an airport rental company. Some of the off sites are located downtown and are much more expensive. Check web sites such as mousesavers and disboards, they have the discount codes that can really bring the prices down.