Buy a vacation package. Packages can include hotel, flight and rental car services. Because you are purchasing in bulk, you will save money.
Contact a Croatian travel agency. Croatia has certain rules and restrictions concerning car rentals coming in and out of different areas within Europe. The travel agency can help you plan ahead to avoid any setbacks or frustrations.
Contact a car rental agency. Most international car agencies have offices in Zagreb. Make a reservation by phone or online. Pick up your rental once you reach Zagreb.
Purchase a rental at the airport. While Zagreb may be an old city, it has amenities just like any big city. After your flight lands in Zagreb, go to one of the car rental offices or kiosks located inside the airport.