I didn't see this choice available, but we stay at a WDW resort (usually Boardwalk, although last time we tried Pop Century) the night before. We rent a car from Budget, then return it to the Port Canaveral location as a one-way rental the next day, taking the Budget shuttle to port. When we return, the Budget shuttle picks us back up and we rent a car for the drive back to MCO (sometimes with a stop at the Boardwalk's ESPN Club for lunch before heading out). It's a bit of driving, but we enjoy the experience. We've never had to wait more than 15 minutes for the shuttle. Plus, for us, it was less expensive that taking the Disney transportation. We rented an economy both ways and were upgraded to mid-size both ways.