We had a wonderfull stay in Florence and it was mostly thanks to the flat. It is super well located, basicly 15 min from everything in the center. We have been welcomed warmly and we were able to enter the flat earlier and to stay longer to fit with our plane schedules. The only negative point is that the street is quite noisy in the early morning (normal because of the central location), so not possible to let the windows openned but the air conditionner is also noisy - better take earplugs :)
Anyway, we absolutely recommand !