For Los Suenos we use MROC. It takes a couple hours to drive from the airport to the marina but it's an easy trip on well maintained, 2-lane roads. The scenery makes the time go by fast. There's a small heliport approx. 100yds from the fishing boats at Los Suenos so if your pax are in a hurry a helo charter could be an option. For the crew, if you're there for more than 2 nights, I highly recommend staying at the Los Suenos Marriott. For <2 nights, the Marriott near MROC is a better choice.
MROC in CRI. Call Rick at GTS 866-995-5656. Great handling.
I called down to Tropic Star about 6 months ago and talked with a gentleman who was fairly airplane saavy. There is a runway at Tropic Star, but it's gravel and about 2500' long. He recommended we fly into Marcos Gelabert MPMG, and then the pax travel by boat (or Seneca maybe?) to the lodge.
IIRC, he said MPMG was like an old military base that was converted into a GA airport a few years ago. Runway is 5906' x 98' and elev is 31'.