I am thinking about renting a car and dropping it off in Split and taking a ferry from there with a stop in either Hvar or Korcula for one night, and then onto Dubrovnik. Is this doable? Rick's book says some ferries are only available certain days of the week and there don't seem to be many departure times. Anybody have any experience with this?
It's true--we had to stay in Kortula a day or so longer than we planned because the ferry didn't run every day--especially after October 1. Here's a site where you can check the schedule:
Jadrolinija Ferries Croatia
Unless you can return your car by mid-morning, it may not be worth trying to include an island. If you could catch the 11:30 catamaran, you'll arrive in Hvar at 12:30. That gives you an afternoon and evening. You could then take the 06:30 catamaran arriving in Split at 07:30 and catch a bus to Dubrovnik arriving early afternoon. If you miss the 11:30 catamaran to Hvar, the next one departs at 15:00 and doesn't get you to Hvar until 16:00 or Korcula until 16:45 (plus 1 hour bus ride to town). That's too little time for the effort, in my humble opinion. Spend a night in Split instead. The above times are for summer schedules (until September 30), after which logistics become more difficult.