Recommend you sit down with the Developer of the Project(s) you are interested in, and let them show you what they are using then explain the building code requirements. I have a place that is about a 5 minute walk from the beach here in Cortecito, and the only area of construction I see that "could" be a concern is the glass. None of it is hurricane rated. I already knew this before buying, but it isn't really a concern (with me in my situation).
I have a home at a beach in NW Florida, and it is 100% hurricane rated. It was expensive. Having said that...Hurricane rated does not provide the same level of protection from Tornadoes which spawn off Hurricanes when they come ashore. Nothing much in building structures can protect you from a Tornado that has you in it's path, and I have yet to see a house that is built to withstand a Tornado. However, the good thing is I have not heard of many tornadoes in the DR, but then again I have not been here very long. Final issue if your place is close or directly on the water.....surge which will definitely result in flooding to some extent.