Hi Alden,
We have been in PR for about seven years. We bought a home way back in the bush without city services. Since it seems like you will need your time to write, I suggest you stay near or in a sizable city. Hear on the eastern side of the Island I would suggest Fajardo, Caguas or Humacao. Lots of people rent out small apts attached to their homes. Be prepared for very expensive electricity and make sure your flat can get liberty cable. They provide the best tv, internet services. If you are going to buy a car here be prepared to pay more than in the states and experience high registration costs. In your flat, check for hot water, it's not a given here. Check screens, amps coming into the flat, many places in PR are under powered and can play havoc with power hungry appliances and electronic equipment. Check the weather, know your rainy seasons and average temperatures. PR has mini eco-systems all through it. Although outback living is much prettier, it requires a lot of time to keep things operating well. A flat in a city should be a lot easier.