I also think Swan and Dolphin may have some charge for parking (or maybe that's included in the resort fee?). When I've stayed at the Swan/Dolphin in the past, I've done the Mears shuttle. I guess it does depend on how many people you have, but a taxi to that area runs around $60 each way.
You can see the mears prices online - I think their website is Mearstransportation.com. Kids under 3 are free, kids 4 - 11 are $26 round trip, and adults are around $33 round trip. There's a way to get a $3 off coupon too - don't remember how I got this but worth looking into.
There's also towncar type transport. That would run more than a taxi, but be more comfotable. I've nevery paid for this, so don't know what it would cost.