The only time I needed more than a U.S. license and passport was my first arrival into Milan, during peak COVID. I went to pick up my sport wagon -- booked through Fox for only $198/week -- at what ended up being an offsite "local" (Italy-specific) partner which required an international license, noted in very fine print in the rental contract that I never bother reading.
After arguing with them for 15 minutes, I walked over to the nearby Sixt (expecting to get gouged for a walk-up booking) and they rented me a car for a still reasonable $250 -- and mentioned how that runaround happens to visitors several times a month. Lesson learned: if you rent a car in Italy, make sure it's one of the large global companies that don't pull the international license bollocks on you.
After arguing with them for 15 minutes, I walked over to the nearby Sixt (expecting to get gouged for a walk-up booking) and they rented me a car for a still reasonable $250 -- and mentioned how that runaround happens to visitors several times a month. Lesson learned: if you rent a car in Italy, make sure it's one of the large global companies that don't pull the international license bollocks on you.