Orlando/Universal--Car Rental Recs?

[elletr13]

Hi All,

Going to Universal Orlando in October with my husband, parents and sister (YAY Harry Potter World). We'll be there Friday night-Tuesday afternoon. While we're planning on spending most of our times at our resort and parks, I do know we're planning to go to Cape Canaveral one day, and Tuesday my husband and I don't leave until 4 PM, so we have a lot of time to kill. 

I'm thinking we may need to rent a car for getting to KSC/the  cape--any suggestions on the cheapest place to do so?