Hello Roberto and Kevin!
Thank you for the advice. In regards to the IDP, the process looks pretty easy and inexpensive. Is this what you are referring to? http://www.dmv.org/international-driver-permits.php
For the ZTLs, I'm assuming we would be given a ZTL pass from Avis to get through Rome when leaving Rome and would need to be careful when entering Pisa (or wherever we drop the car). We are staying outside of San Gimignano for a few days, but would like to have the car to explore the country side. Does renting a car sound like a bad idea? (We could ditch the thought of the car and go back to trains and buses, but it feels a little less "free" to explore.)
When I used the Michelin map, this is what it came up with:
- Rome to San Gimignano Bnb - 281 km, 03h24, and 37.17 € for gas consumption and tolls
- San Gimignano Bnb to Pisa Avis - 74 km, 01h23, and 8.17 € for gas consumption and tolls
Of course we would do some driving in the middle, but it didn't seem too outrageous.
We've never rented a car in a foreign country. Let me know if you have any other advice as we are new to this.
Thank you,
Amanda