painters
Typically, most work here is contracted to the lower class. Some of those are hard workers and dedicated, but generally, even the best lack any serious training or professional experience. Hence, most workers are relatively uneducated in the work they do. When was the last time you ever talked to a "mason" who has even so much as read a brochure let alone an entire book on the subject. Professional training or professional type experience-almost nonexistent. Hence, labor is considered to be quite cheap, although it is difficult to find anyone to do something "right." The vast majority of Dominicans are not accustomed to paying for and getting quality.
My opinion is that the cheap labor is not always so cheap. For instance, hire a "cheap" painter and not only will the job take much longer than anticipated, cost more than it should, and come out worse than desired, the paint will peel before it should(the metal bars on our house were painted without primer and is already starting to come off in places less than a year later), colors may come out funny, paint will be watered down by maybe a half, the trim will also be painted or splashed the main color(Oh, you didn't want me to get paint on the trim and floor- I can spend three weeks chipping dried paint off the floor and repaint the trim-in turn getting paint on the main color and floor starting a vicious process). Of course, you can always stand over them and resolve some of those problems, but then again, isn't that why you hired them-to do the work? Also, finding someone to trust in your home is a problem. As an American living in Santo Domingo, with a decent, but limited income, I usually resort to doing such work myself. At least that way, I know it is done the way I wanted it.
A need for your kind of work? yeah
A demand? dunno
If your idea were to work, my opinion is that you would have to cater to the upper middle class and upper class which although greatly outnumbered by the poorer, are alive and well in this country.