For one the legs of our european honeymoon.. Nice, France to Rome, Italy.. we wanted to rent a car simply because the road goes right along the mediterranian coast which we thought would be a great drive. Problem is, most companies charge a 800E drop off fee, or won't allow one way at all. Is there ANY way around this? Or some other way of doing this so we can still enjoy the drive?
Have you only been checking the bigger rental companies such as Avis or Hertz? Some of the smaller local ones might not have the same restrictions if you rent a car in Nice, drive it as far as the Italian border. Take the train or a bus over the border and then rent a car on the Italian side all the way to Rome. Just an idea, might not be possible but worth a try.
The idea makes sense, but as Nice is so close to the border, i'd get a train/bus to ventimiglia (on the italian side of border) so getting a 1 way rental from there to Rome would make sense. In fairness, the train all the way to Genoa (and even La Spezia, although allot is tunnels) follows the coast closer than the road. A one way car rental from Genoa to Roma would probably be a lot easier to arrange as it's between two big cities