dr52, you might want to try sending a PM or Email to Hillbilly, who lives in Santiago and is very knowledgeable about services, etc., available there. Find one of his many posts and click on PM or Email. In this way you can send him your questions.
I believe in this field everyone has to undergo his own experience to later take control of the situation. It is not wise to expect someone to refer you people able to. Experience shows that people behavior's change depending of the situation. My best friends in the DR refuse to recommend me anyone base on their and my experience. You may make mistakes but you'll learn from it and that is the most important. Good luck
Pascal