With so many B&Bs in Florence, you can easily be overwhelmed trying to choose one that works for you and for your family. Most provide some of the best service and rooms in Italy without the large price tag--in fact, it can be more fun to stay in a cozier, more welcoming environment. Italian hospitality is some of the best in the world, and these B&Bs offer you the feeling of being among family when you stay there.
You might want to consider La Signoria Bed and Breakfast Firenze. This bed and breakfast caters to travelers of any persuasion, and you will also find that they wish to keep you full and happy with a hearty breakfast and a fantastic location near all of the important sights that you have to see. It's an especially personal hotel where you will find a staff happy to help you with any of your needs.
Another B&B that takes amazing care of its guests is a Florence View B&B. Harkening back to the days when a guest was treated like a member of the family, you'll find plenty of reasons to stay here--not only is there an amazing breakfast, but the Duomo is only a few minutes away.