If you don't want to drive yourself, then you are going to have to get a cab or a car service. A car service will be about $180-200 r/t plus tip. Sanford is much further out than MCO..takes about 50 mins to get to RPR from Sanford. We just did it in April.
When flying into Sanford, you have to realize that although you probably got a terrific airfare, you are now going to have to pay for transport to your resort.
There may be a shuttle through American Coach of Orlando. I do remember seeing them at Sanford Intl, and then around some resorts. So you may want to check into that to see if it's an option.