The daily charge at any of the parks is $30.00. They will actually charge you $40.00, but when you return the
ECV and key they will refund $10.00. If you go to more than one park in one day, you can show your receipt and not have to pay the $30.00 again.
The only potential problem is that
ECVs at the parks cannot be reserved, so if you are not there first thing in the morning you might not be able to rent one.
If you are going more than one day, you may be better off renting an ECV from an off-site company. Some information for off-site rentals are:
Here are the urls:
Care Medical:
http://www.caremedicalequipment.com/
Walker Mobility:
1-888-726-6837
www.walkermobility.com
RANDY'S Mobility is in Kissimmee 407-892-4777
http://randysmobility.com/
Colonial Medical
http://www.colonialmed.com/about_cms.html
I have used Walker a few times. They will ask for a credit card and charge it the day before arrival. They will deliver the ECV to your hotel bell services before your arrival and pick it up there after your departure. Their rates, especially for longer than a week, are much better than Disney's. Also, their scooters are much better.
Randy's has better prices than Walker, but they require you must be present when the EVC is delivered and picked up, and have to sign a waiver of liability.
You don't say if you are renting a car or what. If you are using a car for getting around, the ECVs break down into five pieces, the heaviest about 39 pounds. They take about a minute or so to take apart and about two minutes (once you are used to it) to put it together.
If you are staying on-property almost all the Disney-provided transportation can handle ECVs.