Hey mbriskin, I am from Costa Rica living in the US but I have a Cabin in Playas del Coco. I can tell you that the town of Playas del Coco is the biggest in the area (not really big at all) it has restaurants, plenty of souvenir shops and a couple of dive shops. Since your daughter just got certified, Rich Coast Diving usually takes inexperienced divers to a local dive first to get a feel of their abilities. If that works out you can probably schedule the Catalinas islands to the the mantas....lots of spotted mantas and giant turtles. You can see LOTS of sharks if you go to the Murcielago (Bat) islands. You can probably book these dives with Deep Blue Diving or Rich Coast Diving, they are a lot of fun. Water temperatures are fairly steady at around 75 F and visibility varies...some days are better than others, it's just luck. The nearest airport is Liberia Airport (Daniel Oduber Quiroz Airport) 20 minuts from Playas del Coco. For other activities I have used a local guy, Henry Zuniga (tidewateradventure@gmail.com), who has his own tour business. He treats all of his customers like kings. He can pick you up at the airport and for awesome prices take you lots of places like "Las Hornillas" volcanic site hot water springs and volcanic spa mud baths. Another place is "Canon de la Vieja resort" you can do: white water rafting, canopy tour or just relax at the bar/pool. If you feel like doing things closer to the culture, visit "El Chapernal" Ox cart rides, horse back riding and awesome pools. Don't forget to visit Conchal...cristal clear waters great for snorkle and also Playa Grande sea turtle reserve (middle of the night giant turtles come out to lay eggs)
Well...there you go...not just awesome diving...awesome everything !!!