Traveling documents to enter Croatia:
A passport or some other identification document recognised by international agreements. For information you can call the Ministry of Foreign Affairs of the Republic of Croatia 00385 1 4569964

Medical Service
Foreign tourists do not pay for the medical services if the "Health Care Convention" was signed between Croatia and the country you come from. Expenses of health services provided to people coming from the countries with which the Health Care Convention was not signed, are charged directly to users according to the price list. There are some hospitals and clinics in all the major towns and health centres, as well as pharmacies, in all the smaller places.

Credit Cards and Cash Machines
Credit cards are accepted in many places but NOT in all.
Some places still have the old credit card machined which take only the relief character credit cards and not the electric ones.
So you should always have some local currency, the KUNA, or euro with you.
Most islands but NOT all have cash machines, but it can occur that they are out of use or that they are out of money,especially in the peak summer period when the demand is huge.
So, as i wrote earlier, it is always best to have some cash with you.

Accomodation
Crosailing, if told on time,can also help you find accomodation prior to your getting on the boat or after the criuse.