My family of 5 (3adults,2kids) had a marvelous stay with Stefano. He met us exactly on time and showed us around. The apartment is on the second floor and you can arrive by stairs or a very modern elevator.
The apartment was spotless, well equipped, and so quiet. We were in the heart of the city but once inside, you couldn't hear anything!
The location of the apartment is perfect. We walked everywhere. The Duomo is less than 5 minutes to one side and Ponte Vecchio is less than 10 to the other side. There are restaurants everywhere and if you need a bus, it's 200m away.
Finally, in case climate is important to you, the apartment has 4 air conditioner units. We turned them off when we left and it took 30 seconds to cool the whole place when we came home. So comfortable!
I HIGHLY recommend staying at this apartment when visiting Florence!!