Traveling with children - rent car or take trains?

Most likely from Florence to citta di Castello to Perugia to Rome and back to Florence over the span of two weeks. The train doesn’t go into Castello, but my family may be able to fetch us from a train station if we don’t rent a car for that leg.

Having a car in Rome or Florence is difficult. Driving has all sorts of perils from ZTLs to impossible parking. Even Perugia has ZTLs, I think. Some of the legs you need to take are on inexpensive regionale trains and others (like Rome to Florence) can be purchased in advance at steep discount. Your kids ride free under the “Bimbi Gratis” program, depending on which tickets you purchase. You will need to weigh the charge for a fully insured (super coverage) car plus gas and tolls against the train fares, which you can research at www.trenitalia.com.

Perugia has ZTLs that cover most of the historic center and parking, too, is impossible unless you're comfortable leaving the car on the outskirts and taking the minimetrò up into town. If you're staying in Perugia, you won't need a car, since the city center is totally walkable and much of it is a pedestrian zone.

Thanks all. We’re not planning to drive within any cities. Just trying to figure out cheapest way to get from one city to another. We’ve always taken trains, but I’m not sure it’s economical with four of us.

There are other advantages to trains besides cost, particularly with children. They can get up and walk around and not have to be strapped in. The train may sell food. There is a bathroom. The train puts you off in the city center. My kids really enjoyed riding around on trains last year at age 8/11.

You can rent in Florence when you leave Florence to drive to Umbria. You probably want to have the freedom of a car while you are staying in Umbria, to visit your family in Città di Castello and also to take day trips to the many cute towns there (Assisi, Gubbio, Anghiari, Spello, etc.). The only recommendation is not to stay in Perugia with the car during that period, but rather stay in a smaller town (Assisi for example) or even out in a country hotel/villa. On the day you visit any towns just park the car in the many lots outside the city walls. All those old towns have ZTL, not just Perugia.
When you visit Perugia there is a multistory parking structure on Piazza dei Partigiani, next to the bus station. From there you can walk up to the city center up the hill using the underground escalator which will put you inside the Rocca Paolina fortress next to Piazza Italia. Just set your GPS for Piazza Partigiani.
In Rome you won’t need the car either. You can return the car as soon as you arrive in Rome from Umbria. If you prefer to return the car in Umbria and go to Rome by train, you can return your car in Perugia or Foligno (Europcar).
To get back to Florence from Rome, the train is the fastest option.

We do cars in Italy with our kids because we've been able to book them for free with air mile points, which saves a lot off of train tickets x 4. Also, we were staying at places and going places not on regular transit routes. The upside was that the car had air conditioning when nowhere else we went did, the downside is that European cars (and I've been in a few dozen over the years) have very high windows in the backseats. So they kids were a bit bored in the car because they mostly see sky, but usually fell asleep. The time we took the train from Lucca to Florence and back, they were squirrely on the train going in, and fell asleep on the train going home (9 & 12, girls).

You have to look at what you're doing, how long you're travelling, and the cost. Certainly going major city to major city, the train seems the best (depending on price).

Just want to mention that, except for the high-speed train from Rome to Florence, the trains you would use from Florence to Arezzo (Citta di Castello area) to Perugia to Rome would most likely be inexpensive regional trains.