We have stayed at Alessandro's apartment for 3,5 months in Florence. It was an amazing experience. The apartment's location was perfect for us, you can reach the city center in around 15-20 minutes by public transport, or 35-40 minutes on foot, but we really recommend the Mobike bike sharing service.
There are great restaurants and bars around, with very few tourists, so you can experience the "true" italian culture a little bit better. The neighbourhood also seemed quite safe, we have not had any conflict with anyone during our stay.
Alessandro's brother welcomed us, the apartment was clean, and very well equipped. They (Alessandro and Enrico) have provided everything for our stay from kitchen equipment to cleaning tools, towels, etc... (you have to clean the apartment a few times in 3,5 months).
The dishwasher was a pleasant surprise, and the big (covered) parking place was very useful. Wifi was around 13Mbps most of the time, so you can easily stream movies, the connection was stable. If we had any questions, Alessandro has responded to our messages quickly, and was very helpful.
We cannot write any bad thing about the apartment, maybe I could mention, that you will hear every ambulance driving with sirens on the streets, but it is not a big deal, you can get used to it, especially if you are from a bigger city.
Also the view is pretty nice from the apartment, because you do not face the streets.
We really recommend this apartment for everyone, who visits Florence, you will have a great time.