The best way to get to Tarcol Lodge is by private car.
You could rent a car in San Jose and drive there or you can book a tour with Rancho Naturalista and split the time between the two lodges.
If you do the latter they will furnish the transportation and meet you at the airport or your hotel .
You can take a boat tour on the river to see the mangroves and more crocodiles.
The guide may get out of the boat and offer a croc a dead chicken.
Don't try this yourself.