Hi Yippy,
Diving in the summer is fine. The rain doesn't effect the vis. I have dove from Playa Del Coco around 15 trips winter & Summer. La Puerta del Sol is a nice small hotel and is 5 min from everything. Super Clean and not expensive. I dive with Rich Coast Diving. They can set you up with a Hotel /Dive package. Bat island has both Bull Sharks and a Manta Cleaning Station. They will want to see your skills on a local dive before they take you. It can be an advanced dive with some crazy surge & currents. Town is small but a fun safe place it eat and drink. Up the road to the right of the hotel is another group of restaurants & a supermarket. I walk everywhere. Taxis are 3 US dollars to restaurants outside of town. Have a Great Time!! Brenda(owner) from Rich Coast Diving can answer any Questions you have.