Renting a car always is a good idea, there is a lot to see in the area and it makes you flexible.
Public transportation is good and there is a bus company who does two direct buses from San Jose 8 am and 2pm. The ferry is the best access two our area, but there is a way also over the friendship bridge more up north.
Also shuttle buses are traveling from San Jose and other places to Montezuma one or two times a day.
One of the shuttle companies also does a shuttle bus taxi boat connection threw Jaco what last 3h.We had guests who loved it and saw whales and dolphins.
The fastest way getting into the area is by a smaller connection flight with Sansa or Nature air to Tambor what is about a 30min. and 30min. from the airport to us, check out there websites or let us book for you without any extra charge.