I bare boat chartered through "Sailing Holidays", a company that I found at the London Boat show. A big mistake as they are geared towards flotillas. They contracted the boat for us from "Sail Croatia" which we did not figure out until we got there. Be careful, charter companies do quite a bit of sub-contracting from each other. Sail Croatia supplied a Jeanneu 37 and it was OK. The bimini supports were in the way of the primary winch so the handle would not spin all the way around it, bad. And our check in/out was contracted to yet another charter company. It was a crazy way of doing business.
I would not recommend either of these companies. Sail Croatia or Sailing Hollidays.
We did enjoy our sailing area, the Kornati Reserve north of Split. We received our boat in Kremik which is north of Split. I would research which charter companies are based in Kremik as they all seemed pretty good there.
Three questions ask any Croatia Charter company
1. Do you have your own staff that will do the check in/out and support?
2. Is the boat in your fleet or does it belong to another charter company
3. How long have you been doing business
There is an epidemic of Charter companies in Croatia that just pass contracts along and really don't operate and maintain a fleet. Avoid them if at all possible. It is going to take some research to bypass all the fluff charter companies.