Depends what you drink. If you drink Rum then drinking your own bottle or buying a bottle should be the cheapest. In Sosua the chair should be free if you buy something. So if you eat but bring a bottle of rum your chairs should be free. If you bring a bottle and just buy set ups your chairs still might be free. But a lot do not charge that much for a bottle if you buy from them.
If you buy beer some places only sell the small ones. So it is cheaper to buy the larger ones if possible. A lot of places really don't mark up beers that much more compared to buying them at the store.
I have brought my own cooler full with ice and drinks to Sosua many times. I am not sure if it is always worth it or not. I end up tipping a local kid to bring it to the car and back. Plus the cost of the ice. If you are with a group and have a mixture of water, soft drinks and beer it might be worth it. Plus if you want anything they do not normally sell.
I normally go to Sosua if I am getting in the water. I go to Cabarete if I want to hear music, watch sports, etc.
I always go to the same place in Sosua and get good service. I eat there the majority of the time.
In Cabarete I go to lazy dog a lot. I also go to big kahunas and the Irish place osheas. There are hotel rooms on top of big kahunas. I forget the price and am sure it is loud till late. But very close to get home.
I don't know anything about where to eat breakfast or places in Sosua away from the beach. Once the beach in Sosua starts closing down I go home or go to Cabarete.
It is not the cheapest but Sosua ocean village is pretty cool. There are there pools and a nice view. A kids pool, a lap pool, an infinity pool looking at the ocean and 3 water slides. Also a gym and sauna there. A calm place with no music. The beach area is not to big and the waves seem to be rough. I have never entered the ocean there.
