We are in San Juan now. Plan to take the train and bus as much as possble around San Juan. Taxis are expensive for normal travel. I guess the cost is reasonable for the time it takes t go by taxi but more than I wanted to pay to get around. The train and bus system is very good and EVERYBODY that we met are willing and enthuastic to help you find out where to get on and off. Seveal people got off and waked us in the right direction to make sure we didn't get lost!!
Most hotels are in two areas of the beach area. One area (Canado) has more trendy places to shop, eat, ect but the beaches are not quite as nice as the other (Carolina) where there are more beautiful beaches but less in the way of shops.
Old San Juan is not too far from either but the taxi cost about $21.00 one way. Old city is not to be missed and there are a lot of restaurants, shops and activties there as well as El Morro fort.
El Yunque rain forrest is about a hour south of San Juan and beautiful. There are plenty of tours that will take you there.