For all the running around you’re going to be doing I’m guessing renting a car would be your best bet. If you hire a car service for each of your trips I bet you’ll spend more than you would if you just rented a car for your entire stay. If your day trips are all clustered together at the beginning or end of your trip you could rent a car and return it then rent another car (or hire a town car) for the trip to or from the station.
It sounds like you have a lot of plans for your trip. I hope you saved some time to just enjoy the resort. The pool is worth and entire day or several shorter visits during your trip. We try to plan on full day for relaxing at the pool and several afternoon breaks.