Lodging.... Traveling around Italy

March will probably be somewhat "quiet" in Italy, and you should little trouble finding accommodations without a reservation in the larger centres (Sorrento, Florence, Siena).

However, I'm not sure about the Cinque Terre, since the official start of the tourist season usually isn't until 1 April. There may be a few places open in March, and you'll probably have better luck finding something in Monterosso. It's the largest of the five towns and therefore has the greatest number of hotels, restaurants and other tourist amenities. One other concern in the Cinque Terre at that time of year is the weather, which could be somewhat "unpleasant". If you just want a brief look at the Cinque Terre, you might consider just visiting there on a day trip from Florence. That way you'll be able to choose a day with good weather.

You should have no problem finding places without reservations in March, unless the place is seasonal and not open yet. I sometimes check booking.com or some other service the night before check-out to find a place at the next destination. You can book through them or contact the hotel directly.

I would look inside the walls or in the city center rather than near the train stations in places like Siena - the station may be less convenient to the town center for many places in Tuscany and Umbria.

The areas around train stations tend to be the most unattractive part of towns/cities. Do yourself a favor and stay central to the sights. So think of it this way - you arrive at the train station, you get to your centrally located hotel and you have the attractions right at your doorstep every day. If you stay near the train station, you'll have to travel to the sights and back everyday, which gets tiresome.

You should be fine. I usually have a list of 2 or 3 good options on me for each stop. I will either wander by and check the places out once there, or if I am confident of the place, may call ahead or email the day before for a reservation.

Go to
www.bedandbreakfast.it
for hotels and bed and breakfasts around major points of interests in Rome and Florence, including Roma Termini and SMN in Firenze.

I use this website even for smaller cities and towns, but note that sometimes the train station may be far from the center or not there at all.

We've traveled Europe, including Italy, many times with no reservations. As long as you're not picky and are willing to put in the time to find a place every time you move to a new city, then it won't be a problem especially in March.