Pay for ALL available insurance. You will need it if you have an accident! Have you ever driven here before? They drive on the "Left" here! AND on the Right,and in the Middle TOO! Be Carefull,be VERY VERY Carefull!
And please post again AFTER this experience!
You might want to consider visiting Altos de Chavon in Casa de Campo, La Romana. It's about a 1 hour drive from Juan Dolio and is a nice tourist spot. You'll also go by the Cueva de la Maravilla which are underground caves the government's (I think) arranged to be comfortable for site seeing. Last time I went was over a year ago and from what I can see from the road they've done a lot of work on it.
Watch yourself on the roads though, for other drivers and potholes and try to get back before dark.
If you like to see the countryside you could go from San Pedro to Hato Mayor continue to Sabana de la Mar, visit Parque de los Haitises, or just continue via Miches to Higuey and via La Romana and San Pedro back to JD.
You get an impression about the eastern part of the island.
As already mentioned, full insurance, drive careful and enjoy the trip.
LOL last tiem I was in santo domingo I rented a car as well, and I tell you. People there all have no order at all when it comes to driving.. It is the craziest thing I have ever saw in my life. GOOD LUCK...LOL
Drive towards san pedro. Keep on the main motorway and do not go into San Pedro. Go over new bridge over river adn from there to La Romana. On the way to La Romana, on the left is the Cueva de la Maravillas (or something like that). It is on th eleft, after the Soco bridge and well marked. Well worth a visit. Will take an hour. From there into La Romana. Follow signs to the airport and just befoe the airport turn right up to Altas de Chavon. You can have lunch there. On the way back try and get into Casa de Campo. Tell them you are going to eat at the harbour. They will probably keep some form of ID. Follow signs to the harbour. Look at the shops (far too expensive to buy anything!!!). Sit and have a drink at the harbour looking how the other half lives!!! Then back. On the way back keep going straight into San Pedro, past the Zona Franca on the left, and you will come to Jumbo on the left. Stop there and stock up on rum and other goodies for your return. Then home!!! Just be very careful when driving!