Hertz - Rent at FRA, Drive to Switzerland and Italy

I am planning to rent a car at Frankfurt Airport and drive to Switzerland and Italy. I have booked a BMW 3 series with navigation system.

Will the navigation system work in Switzerland and Italy?
Do I need an International Driving Permit
In the US, my wife is allowed to drive for no additional charge. This applies both to gold members and AAA rental rates. Will this also apply in Europe?

Thanks,
Mike

If you get the text-based navigation system (common in the 3-series), then it will work for Italy and Switzerland. I had one thru Sixt.

You MUST have International Driving Permit for Italy! No exceptions. They got strict about four or five years ago.

There was no charge for my friend to drive my rental car thru Hertz in Germany so I don't think so.

You will also need to specificially request the annual Swiss motorway permit; I failed to do this from a rental in the Netherlands a few years ago and had to buy it myself and leave it on the car. Expensive 1-day toll!

You can't specifically request that since the MUC station as far as I know does not keep track of cars that have the vignette sticker affixed to the window. If you don't have it, it's 40F to buy one at the border. MUC will not buy it for you.

Hertz won't let me take a Mercedes or BMW rented in Germany to Italy. I had to switch to Avis.

I distinctly recall all Benzes not being allowed in Italy.. I think it was Sixt that allowed BMW's and not Benzes, but I do believe Hertz extends it to BMW's. I have been there so many times, my memory gets a tad bit fuzzy.