- Renting a Car
If you plan wisely, I'd avoid this option. For one, you have to pay parking fees all along the resort strip of Condado and Isla Verde (or drive around for hours looking for a spot), and parking in Old San Juan is no less fun. Secondly, traffic can be a nightmare in the capital, especially on the way to the old city. However, if you want to canvas the city and plan to hop between neighborhoods (visit the mall in Hato Rey, then the beach in Isla Verde, followed by dinner in Old San Juan ... that kind of thing), then a car will be cheaper than continuous taxi rides. All the big agencies are located in the city, in the airport and at various hotels, and rentals will cost roughly $30-35 a day for an economy car.
- Taking Taxis
The taxis in San Juan aren't cheap, but the taxi union is quite strong, so don't expect fares to go down anytime soon, or for hotels to start providing shuttle services for their guests. The white taxi turístico that you'll find at every hotel and at designated taxi stands charge by zone, with fares ranging from around $10 to $20 (plus $2 per bag if you have luggage). In other words, a taxi from your hotel in the resort strip to Old San Juan and back will run you around $30, depending on where you are. They are, however, reliable, safe, and comfortable. You can also hail metered taxis from the road, which can be a cheaper alternative.
- Can I Walk?
Distances in San Juan can be deceptive. Walking from Isla Verde to Old San Juan will easily take you a few hours, so unless you are really on a budget, I wouldn't recommend this option. Even from the closer Condado neighborhood, it's still a good hour to the city on foot. While you're in Old San Juan, however, walking is the best way to travel, but if you get tired, there is a free trolley from Plaza de Armas that will take you around the city.
- What About Public Transportation?
There are public buses in San Juan (they call them guaguas) that cover all the tourist zones. For example, the A-5 bus will take you from Isla Verde Avenue to Old San Juan in about 45 minutes to an hour, depending on stops and traffic. A 75 cents, it's a much cheaper way to get around, if you don't mind the extra time and a bit of a walk to your final destination.