Multi-country rental car route query

I picked up a Hertz in Geneva and drove to Malaga some years ago, and recall the cost was 1500 euros for a four day rental.
Out of curiosity, I asked AI your question, and it said fee of 250 -1200 euros, depending on company, distance etc.

The best approach is to ask each agency what it will cost for you NOW. Only they would know.

Vignettes are usually country-specific, and you shouldn't expect a rental car office
in one country to provide one for another country.

Any reason you can't take the train from Munich to Salzburg and pick up the car
to start your driving trip from there? Rail transport between Munich and Salzburg
is easy. That would get rid of one country and may reduce the dropoff fee.

Since the dropoff points for each agency may vary, you probably need to contact
each company to try and drill down further. This is more difficult with a one-way
rental since the US call centers will not know much and probably the office at
the starting point won't either, plus the language issues. You can always drop
at an airport and take some form of local transport to get into the city.

Unlikely that a car agency in Munich will provide a car with an Austrian, Swiss, Czech or Slovenian Vignette. That's your responsibility.

You won't be able to get them before your trip because it is linked to your car number plate. Most vignettes issued now are electronic ones bought on line. The days of sticking one on the windscreen are rapidly disappearing in the rear view mirror. Very quick, just a few moments on the webpage.

If you are planning on using the Brenner Pass be aware of major construction and big delays depending on the state of the works. Also a big toll not covered by vignette. Also the tunnels in west Austria are very expensive and not covered by vignette.

Rental cars don't get any byes in ZTLs. Ensure that your agency gives you clear written instructions to avoid the ZTL. I wouldn't expect the Munich agency to have that information - you will need to contact your destination ahead.

The (very high) one way drop off varies by origin, destination and company. Expect high 3 figures or low 4 figures for that fee alone. They can't rent it in a foreign country and need to pay for a driver or two to return it to the hiring base. You pay for that plus the costs of tolls, hotels and meals, and the opportunity cost lost when the car is unavailable for rentals, and the cost of returning the driver(s) to their home base. It is not cheap.

IMO 250 euros is a very big underestimation for a car return in a different country. I would guess closer to 800-1500 euros, for all the reasons given by Nigel. The comments regarding the vignette, etc. are spot on also. Each country issues its own. I would definitely rethink dropping off in a different country.
Re routes, we are old-fashioned when planning drives in Europe and usually get a Michelin paper map for an area to plot out our drives. We like to see the "big picture", and are prone to meandering, so it works for us. But a straight city to city drive should be fine with the online route apps.
ZTLs in Italy are strictly enforced. I would contact the rental company for how to get to the return location. There will be ZTL-free routes to return your car. Or check for an airport map on line. It should indicate car rental places, etc.

My preference for returning rentals is to return them at an airport. Even if I am not flying.
- Airports are usually easy to find and get to. And the rental drop off is usually well signposted.
- Getting from an airport to the city the airport serves by public transit is usually trivial. There will also be plenty of taxis available.

For example, a few years ago I dropped off a car at Palermo airport, then took the train in to Palermo, where we stayed another two days, and then travelled home by night train... It was just so much easier to drive to the Airport rather than having to deal with Palermo traffic,

One thing you have to be aware of is that car rental operates as a franchise system. Europcar in Germany will be a different, completely unrelated company from Europcar Italy. Which is why the car needs to be repatriated. Europcar Italy cannot rent out cars they do not own...

The one way drop fee will vary, a bit, by company and also car class. For what you are planning figure $900 minimum and $1300 or more is not to be ruled out..
Time of year is also likely to be a factor.

Unless you are among the "money is no object" economic class, you may want to reconsider doing a on way rental.