Uma, not sure whether you are hell bent (like I am sometimes) to be an independent traveler on this trip, but I was doing those same cities several years ago, and chose to do Perillo's Deluxe Italy by Rail after I had looked into the same thing on our own. It wasn't really a group thing, other than getting us from place to place on first class trains and booking our hotels for us, and giving us some of the best guides I have ever had on any trip I've ever done. For instance, in Venice, we stayed at the Hotel Danielli, a wonderful property. In the other cities, I can't remember the hotels, except to say they were really nice. We also had a side trip to Siena. What I liked was not having to do all the reservations separately, and we did our own thing for dinner every night. Breakfast each morning at our hotels was included. Worth a look into it.