Hi dpja11, welcome to CruiseReviews. Casanova Frankenstein will be a great source, you can send him a PM, since he lives in Puerto Rico. We stayed at a few hotels there, the price was between $180 and $220 a night. Cas may know of something less expensive, but the prices I've seen are not "cheap". Puerto Rico is a great place and we have normally stayed in the Condado section, but have visited a bit of the island. I don't like driving there, so taking a cab can become a bit expensive. I don't think they use brakes there, just horns, so it scares me a bit
Hope you have a marvelous cruise! Coming in a day early is a great idea. I took a cruise out of San Juan once and flew in the day of. Never again! My luggage took 3 days to catch up to me. I'm not sure where it was vacationing, but trying to purchase everything you need on board is NOT fun. They tend not to carry underwear and other things you don't even think of because you always pack them.