For first timers, we always recommend renting. Gives you the flexibility of checking out the area. Seeing one city/area does not mean you have seen it all. Some people will love living in Santo Domingo, others will prefer Santiago, others will like Sosua, others La Romana or Juan Dolio. You may check out different areas, and renting allows you this flexibility.
For more information, check out the content providing in the Living and Legal sections of this web site. Lots of helpful information that will answer many of your questions.