Staying for 4 full days in Disney at the Cypress Grande Villa.

Here are some questions:

1. Car Rental/shuttle? Car Rental coming in at $600 for 6 day rental...eeek...

2. I specifically need to know where and how to buy theme park tickets.

3. How much for parking at the parks?

4. Thinking of visiting MK, Epcot and Universal Studios. Any ideas on tickets for visiting these parks?

Thanks for any and all help....