B and Bs in Sienna and Florence

Try a website called cross-pollinate.com It is a b@b booking service owned and operated by an American couple living in Rome. They have B@B accommodations in Rome, Florence and Venice. I have used them many time and they are very reasonable. Siena is difficult to find rooms in. I think its better to do Siena as a day trip. Anyway, have fun!!!

Not sure when you are traveling but I would recommend Hotel Il Bargellino (no breakfast, but they have a refrigerator in each room and there's a market around the corner).