This is the place!
We stayed with a family of 4 and this was my favorite AirBNB that we have stayed in since we started using AirBNB 3 years ago. Everything was as promised and the host even left us some milk and breakfast goodies to get us through the next morning. She also sat and went over the best highlight of Florence for us (sights - there are so many, local food, good deals and great street shopping to check out). The location cannot be beat - it's less than 10 minute walk to everything you want to do. Our only regret is that you can only see so much in 4-days. We will be back to Florence to check the rest of it.