According to the Croatian law, at least one person on the vessel must posses valid nautical and VHF licences.
List of valid nautical certificates for bareboat charter in Croatia (PDF).
Charter guide

Itinerary 7-day route

Base info
Turistic tax: Kuna only (10 Kuna/day/person)
Transit log: Kuna, Mastercard or Visa
Security deposit: Mastercard, Visa or cash
Insurance of deposit per week:
150 Eur for boats up to 39 feet
250 Eur for boats 40 – 50 feet
350 Eur for boats 51 feet and more, catamaran Lagoon 440 and Elan 50 Impression
Insurance notice: if made in Garant, the price is
150, 250 or 350 Eur (nonrefundable part)
+ 300 Eur (for boats up to 50 feet)
or 500 Eur (for boats 51 feet, catamaran Lagoon 440 and Elan 50 Impression)
refundable part, for the cases when:
1. boat comes back with empty diesel tank
2. come back with blocked toilet
3. do not come back on time If made in other insurance company, it is necessary to leave the deposit.
In a case of accident, Garant Charter issues confirmation and insurance company gives you back the deposit.