I rent an apartment in a really nice area, close to everything for RD$8,000.00. Three bedrooms, 2 bath., with lots of room. You can find them for less money in other nice areas, you only have to look around and ask a lot.
Also, my uncle lives in Santiago, and he rents a very nice size house in a real good area for RD$5,000.00. In small towns and smaller cities it's going to cost less. Not in places like Puerto Plata, because there are many tourists around that area. It's more expensive to live in places like that.