Bruno Stango is an accomplished and widely-published architect specializing in architecture for the tropics.  His Rosero House is an interesting example of a house designed with extensive outside space and a defining roofline using simple materials.  Based in San Jose, he is also a founding member of The Institute for Tropical Architecture  (Instituto De Arquitectura Tropical): founded in 1994, as a non-for profit association, composed of architects and other professionals. The Institute’s principle objective is to promote discussion and provide study about architecture and urbanism adapted to the tropics.  

EcoArc is a local Ojochal green architect with green designs that use natural materials like bamboo to complement steel and concrete. Christian Rivera and Perceval Spriet would be happy to help design a very traditional or very modern house, as in the Casa Ballena, a beach house with natural character next to the Ballena Marine national park. 

Luz de Peidra is another San Jose architect focused on sustainable architecture, who aims to incorporate nature in architectonic space and design. This includes conserving the existing ecosystems, adapting to the topography without damaging the soil, reducing energy use through passive climatization (shadows and ventilation in the tropics), optimizing natural light, and using local labor where possible.  The firm also considers alternatives for passive energy and the use of natural resources, such as the use of rain water, solar radiators for water heating, and waste reuse and recycling.

Geoff McCabe also has interesting house designs as part of his Eco Village in Montezuma, Costa Rica, further north in Guanacaste. His home styles incorporate many different green ideas. You could commission one of the pre-existing models or customize to fit your particular lot.  An example is the Casa Amapola a 2bed/2 bath tropical cabin.