Known for its amazing white sand beaches, Puerto Plata is a popular resort destination as well as a great place to meet Dominican people and to shop in local commerce.
Taxis are the most expensive option and not really more secure than other choices. Buses are slower, but the cheapest, and, once you understand the routes, the easiest way to get around.
The beach Rent a longchair if you really want to appreciate it, because if you don't, the Dominican will ask you all day long if you want to rent them a chair. The only advantage to be extremely patient and tolerant is that their prices drop down with the time! But as everything else, chair rents are also negotiable.
If you are looking for tourist stuff (paints, rum, cigars, t-shirts, etc.) the best place to go is Sosua, about 10-15 minutes from Puerto Plata.
GWA-GWAs are simple minivan for normally 7-8 persons that can be easily packed to 22 persons and 2 roosters! GWA-GWA are the main common transportation system but not really organised; you can stop practically anywhere along the main streets and wait for one to stop and climb up, the fair is normally cheap, but you'll probably have to negotiate with the driver or the door operator.