If you are have a US passport, you do not need a visa. There was a chance that US passport holders would need to apply for ETIAS authorization in 2025, but the program appears to have been delayed until 2026. It’s best to keep up to date via the website: https://etias.com/etias-requirements/etias-for-american-citizens. If you hold a different passport, it’s best to check visa requirements online.
Yes - you can definitely rely on public transportation to get around (see Travel site). If you do decide to rent a vehicle, we recommend renting when leaving whatever city you have flown into, or even taking public transit to another town and renting a car from there (e.g., renting from Perugia).
Yes - there is lots of parking available at the wedding site.
Please dress nicely! No jeans, please.
Late September can be very pleasant in Italy (not too hot) - however the chance of rain does slightly go up. It’s worth planning for cooler evenings but also warm days.