Also check the all parks passes on the Busch Gardens website. We got four 2-year passes about three years ago for around $1000. Earlier this year I think it was discussed that they were even cheaper. You have to buy four to get the discount.
We went to Sea World a couple of times, Busch Gardens Tampa three times or so. We never made it back to Virginia after the first time, but I think we got our money's worth. Free parking was included.
Sheila