Driving from Florence to Rome

The best way is doing day trips, because changing accommodations too often is time consuming. In the time it takes to unpack, repack, check-in, check out you can drive from Florence to Rome (2.5 hours on the freeway). Since you'll have a car, you need to find accommodations outside of historical city centers where traffic/parking is restricted (such as Florence, Siena and also several smaller towns). Agriturismos are great, alternatively you could find B&B or hotels out in the countryside or outside of city centers. When you do your search, inquire into parking at your accommodations. Most hotels/B&B outside of the historical centers should be able to provide parking. Based on the places you want to visit, you should look for a location as close as possible to the freeway. The most central area for your proposed destinations is the stretch of freeway between Poggibonsi and Siena. From that area (don't go to far from the freeway) you are within 90 min or less from any of the towns you mentioned (Assisi being the farthest). In that area, Colle Val D'Elsa is a pretty town and so is Monteriggioni. Poggibonsi is a little bigger and a little more industrial. Consider however their historical centers are also closed to traffic, so look for something with parking outside of the city walls (if you want to stay in town). There are also plenty of choices outside of town in the countryside (both agriturismo and hotels/B&B). It really depends on you if in the evenings you'd rather be somewhere secluded with just you and your family, or if you'd rather stay in town where you can stroll around and see some street life.

In addition to Roberto's good advice I would recommend using a GPS. It will make driving so much easier. I sent you a Private Message with a recommendation for an Agriturismo.

We stayed in Pienza at an agriturismo, as it was central to the towns that we wanted to see. We didn't get to Volterra or Assisi, but we also really liked Montepulciano. If you like wine tasting (and Sangiovese), the Montalcino area is a good place to go. We wound up focusing more on seeing more towns than spending a lot of time in each, so we definitely want to go back. On our way down to Rome, we also stopped at Civita de Bagnoregio (only accessible by a ped bridge and virtually untouched by time) and Orvieto. We really debated on staying in an agriturismo vs. a place in a hill town and we were glad we did the former -- easy parking, easy to get in/out (the approach in/out of some of the hill towns can take a bit of time, especially if its a weekend).

Thanks so much. Can you recommend an agriturismo. We tried one and they were full. For various reasons we have not been able to plan as far in advance as I would have liked. Thank you. Charlie

Look up here in these websites: www.agriturismo.it www.agriturismo.net www.agriturismo.com Location is key. Some might be located in very secluded farm houses a long distance from the freeways. That will make it difficult for you to efficiently day trips to the various locations. Therefore before you book one, study carefully on Google Map where their location is with respect to the freeways entrances. Although the distance in Km may not seem far, some roads in Tuscany are so curvy and narrow that you won't be able to drive over 40 km/h (25 mph). Try this one if they are available for your dates. It's only 5 min from the freeway entrance at Badesse and about 20 min from Siena. Within an hour you can be virtually anywhere in Central Tuscany and Assisi (Umbria) is less than 2 hours away: http://www.agriturismo.it/it/agriturismi/toscana/siena/AnticoUliveto-AzAgricolaBiologica-7080100/index.html This is their website:
http://www.anticouliveto.it/?lang=en

Roberto's right on the money. We turned our Hertz car (reserved thru AutoEurope.com) across the street from the Orvieto train station and took the 75 minute train ride into Rome.
Orvieto's another very popular hill town. Civita is southwest of there and another worthwhile little town to see.