Trip with parents in their 80s

After your Rome time, (or before it, if you’re saving Rome until the end), plan on staying in Orvieto for a few nights. It’s a hilltown (OK, city of 20,000) with several remarkable sights, and a cathedral with striking black and white stripes on the outside, along with notable murals inside.

The parking lot is at the bottom of the town, by the train station, and then you ride the funicular up into the town, more then 500 feet up. A shuttle bus greets the funicular to take people deeper into town, although we stayed at the wonderful Hotel Corso, which is closer to the funicular unloading point, and was within walking (and rolling suitcase) distance. The layout allows for easy walking, and places for sitting without having to go very far. It’s a mesa on top, so relatively flat in town, once you get off the funicular. With a car, you might venture into the countryside of Umbria; we didn’t have a car, but Orvieto kept us busy for our two-night stay.

I definitely like the idea of staying in a Tuscan town, if you have a car. Then you can get to so many beautiful places.
Consider Castello di Verrazzano - a wonderful winery tour with an incredible view, and then a glorious lunch! We have done it twice and would do it again if we got back to that area.
Also consider Deruta - where they make all the beautiful dishes! Assisi lovely, as are all the hill towns.

You want to go off the beaten path? You might consider the town of Rieti and the Sabine Hills, very close to Rome (an hour or so and not on the tourist trail.

https://ecobnb.com/blog/2021/08/sabina-olive-villages-italy/

https://italoamericano.org/sabine-hills

https://www.latorrettabandb.com/the-area/

The area is famed for its oil and you could try the new oils at that time of year..

Orvieto could work well for this. The funicular gets you up from the train station, and there’s a bus from the top to the Duomo area, so your dad wouldn’t have to tackle the uphill walk. The historic center is also fairly manageable once you’re up there.

Many, dare I say most, hill towns may be an issue with a car, since parking is only below the hilltops and necessitates walking uphill just to get to the historic areas, which are hardly flat. I also wonder how scenic those Tuscan hills are in December, when trees and vineyards are bare of greenery. I don't know if any crops are grown in December.

Places that may be more suitable are Bologna, Naples and Salerno. All are accessible by high speed trains. Bologna is pretty flat, has some worthy sights and is a rail hub, making it easy to take day trips to nearby towns. Ravenna is a bit far but well worth it for the Byzantine churches and wonderful mosaics. Ferrara, Modena, Padua and Parma are closer and each has lots to offer. Naples is mostly flat, has an interesting history, lots to see, a National Archaeology Museum that's a wow, and easy local train (well, metro really) access to Herculaneum, similar to Pompeii but much smaller and easier to walk. You can stay in Salerno and take the bus to the little towns sprinkled along the Amalfi Coast, busing from one to the next. If you want to drive, you can rent a car in Salerno. It's somewhat challenging to drive, but if it's not yet crowded with holiday tourists, it shouldn't be too bad. To give you an idea - here's a chronicle of my experience in mid-February.

The only place where a car is recommended is if you decide to visit Tuscan hill towns. You could rent a car in Rome and head north. Between 15 November and 15 April you must mandatorily carry chains or snow tires practically in all of Tuscany, therefore make sure the rental agency provides them for you. When I go to Italy during that period I always rent SUVs, which you should do anyhow with 4 people in your party. I use the broker below:
www.autoeurope.com

Last summer I took relatives around while I was wearing a CAM boot (not while I drove of course) so it’s doable. Parking is always outside the city walls (ZTL) so a little walk is required, but it’s not too bad in most towns. Cortona is kind of steep, but you don’t need to walk to the very top. If you decide to visit Tuscany prepare a list of towns and I’ll tell you where to park and if the town is a bit too much for your dad.

Don’t rent cars for Sorrento/Amalfi Coast area or any big cities.

Vineyards in Tuscany will be bare but many trees are evergreen (olive trees and cypresses and pine trees) and the grass is always green, so the winter landscape of Tuscany will still be enjoyable. There must be light fog or overcast skies at times however.

How many NIGHTS will you have on the ground in Italy?

but mostly go day by day and book lodging daily as we go.

This would make me very nervous.
If you are planning to visit off the beaten path/rural locations just know that there are limited options- only so many rooms/hotels in most small towns and some may even be closed for the season in December.
It gets dark early in December- I would not want to be driving around Tuscany or Umbria in the dark looking for a place to sleep.

If you are going to rent a car and drive make sure all drivers have an IDP-required by law- along with their US driver’s license.
Be careful leaving luggage in the car if you stop en route- take your valuables with you.
Do your homework regarding driving in Italy- ZTLs, parking, speed cameras, tolls, etc.

Do you intend to spend any nights in Rome?
If so I would put all Rome nights at end.

Something like this:
Arrive FCO- pick up rental drive to Orvieto (1.5-2 hr) that’s as far as I would want to drive after an overnight flight.
There are a few hotels in Orvieto that have parking.
Spend 2 nights in Orvieto- it’s a lovely town, basically flat once you are up in town
(The funicular is currently closed for maintenance- no idea if it will be open in December)

Then choose a base in either Tuscany or Umbria and stay for 4 nights. Take day trips from that base. Make sure your lodging has parking.
Spoleto is a larger town but well located for day trips to Assisi, Spello, Bevagna, Deruta.
We really like Pienza in the Val D’ Orcia- lots of day trips/drives possible from there. There are several hotels here that offer onsite parking. Pienza is flat- easy for your father to get around.

Somewhere just outside Siena could work as well.
Again keep in mind how early it gets dark and plan your day trips accordingly.

You could drop your car before returning to Rome (Spoleto- Hertz, Chiusi- Avis/Budget) then train to Rome for the final 3? nights.