I found Hotel Perseo via TripAdviser. Given its relatively low cost and its central location I was v impressed - great value for money. While not 'fancy', Perseo is clean, rooms (and ensuites) are fresh (look recently renovated), staff v friendly and speak excellent English. Breakfast (included) was diverse too. A stone's throw from main train station and the awesome Duomo! Location meant you could pop back and drop off shopping or have a quick rest before venturing out again for afternoon/evening. Hotel also happy to book tix to Uffizi, Gallery of Academia, Tuscany etc in advance for you. Consider buying Firenze card - covers many entry fees and you can jump in express lane, bypassing 2 hour queues (and that was during spring season!). Enjoy!