I would begin by listing all of your requirements for your new green home and comparing these requirements to what is available from prefabricated home manufacturers.
As an architect, I would strongly recommend that you hire an architect near you here in the continental United States to work on the details and help you organize your specific requirements.
Many architects such as myself are NCARB certified and can practice in Puerto Rico since it is part of our great country.
For your knowledge, contact different contractors in Puerto Rico. You might find that with the possibly lower labor rates in Puerto Rico, you will be able to have a home custom-designed and built to meet your exact requirements for the same cost or slightly higher than a premanufactured home.
For more information:
Read "I am going to be building a container home in Puerto Rico and am looking for a construction company that is proficient with this process." a Q&A answered by Polly Osborne.
Also, read "We're building a prefab home in Puerto Rico. How can we keep it cool without central AC?" a Q&A answered by Mark Schrieber.