We (2 of us) want to go to Dubrovnik after spending sometime in Venice. As we do not want to fly, it appears that it is fairly expense, we like to drive and Croatian coast looking interesting, I have read that once in Croatia there are not any drop off fees from many of the rental agencies, but it looks like if we rent a car in Italy then drop off in Dubrovnik there are substantial fees. We would also like to drive into Montenegro once we settle in around Dubrovnik. So the big question is how do we get into Croatia to then rent a car? Would like to avoid going all the way to Zagreb if possible. I will also post on the Eastern Europe site. Thanks to all in advance.
If going in season (approx May thru September), Venezia Lines runs a hydrofoil about 3 times per week from Venice to Porec and Rovinj. My recollection is that there are more rental car options in Porec. Another less direct (and possibly less expensive) option would be train from Venice to Trieste and then a bus into Croatia (Porec or possibbly Rijeka) to pick up a rental car. Edit: The hydrofoil departs for Croatia late afternoon (around 5:00), so you'd need to plan for a night in Istria if you choose that option.
Another question would be "how much time do you have?" It is quite a distance from Venice to Dubrovnik, Google says 8 Hours, but I would plan on a two day trip with delays and time to stop a few times (Many things to see along the way) so for there and back, plan on a week of travel and time around Dubrovnik if you are driving. There have been some budget flights in the past that would get you there same day, but for Ferry/Bus/Car combinations it will be time consuming.
If your objective is to get to Dubrovnik as quickly and cheaply as possible, you might consider an overnight ferry from Bari, Italy. You can check schedules at www.jadrolinija.hr (might only be available a few months in advance). You would need to take a train from Venice to Bari. Once in Dubrovnik, you could rent a car for a few days to drive around the area and visit Montenegro. Other option is train Venice>Trieste, then bus to Rijeka and pick up car. OR, even more economical, bus all the way from Trieste to Dubrovnik, then pick up car.