Don't ask, just do! If somebody stops you start worrying about permits...Seriously!!! The Dominican way, if you are not sure, is to do it at night time.
I would say yes, but let the builder go through the hassle. However, since this will be in the back yard, you can probably get away with it like the poster above said: Just do it...
Technically; you probably need a permit. Realistically; it depends where you are. If you are in one of the more populated areas, you will probably get hassled; otherwise, nobody will care.
Yes everyones situation is different. We live in Puerto Plata and you need the permit. Its really no big deal. I can't get a permit for one of our patios in back until I finish a section of the house forst. Thats how picky they can be. I was a homebuilder once and i like to obey regulations. right or wrong. Thats just the way I am. People always want the easy way out. My family is Dominican and we do it the correct way. jajajajaja