I went to isla contadora last August. We were thinking about taking the plane but heard from a couple different places that they are always late and sometime even land somewhere else first to drop off supplies.
We took the ferry Sea Las Perlas from Brisas de Amador, Perico Island Causeway. Boarding was 6:45am
All you do is show up they have a tent with chairs under it. There will be a guy at the front sitting at a table you give him your reservation number and he gives you a colored ticket depending which island you are going to go to. The ferry left on time and we were at the island before we knew it.
How long will you be on the island for? I believe if you look on google maps Playa Executiva was our favorite beach. I think the only place that takes cards for eating is Geralds its just up the road from the ferry landing.
Beer was cheap at the supermarket but my wife wanted a little bottle of vodka. It was $14 for a airplane bottle of Finlandia.
Definitely rent a golf cart to get around it is fun to hop around and go from beach to beach. When one beach got too crowded for us we would go to another. ( Too crowded when we went was more than 4 people )
Depending on when you are going, if you are into whale watching or fishing don't go to the tour guide place just go to the beach where the Ferry landing is and ask someone with a boat. ( They will be the ones that shuttle you to the island from the ferry) We paid less than half than the tour place and we were a lot closer to the whales than them as we saw there boat come by us 30 mins after we got to the whales.
Our Captains name slips my mind but if I think of it I will let you know,
If you save money by taking the ferry I saw a nice Yacht take a family out and they came back with a bunch of lobster to cook at their hotel I don't know if it was private or you could hire them though,
Have fun the island is beautiful.