We highly recommend staying at Massimo's place.
The location is a short walk to the bridge that you can cross by foot to access all the touristy parts of Florence.
It is a two minute walk to the Hertz car rental location. (We are so glad we rented a car for a day to drive around Tuscany, visit wineries, take scenic photos, and visit Pisa.)
Massimo and his wife were very accommodating with my wife's sensitivity to fragrances.
The restaurant they recommended nearby was excellent.
The bed and bedding were very comfortable. We slept well.
The place was exceptionally clean.
It's on the ground floor, so no stairs to climb.
The only negative, which is minor, is that the curtains in the bedroom were a bit sheer for privacy, and the window covering in the front window facing the street doesn't completely cover the window. But that was not a big deal.
It was very hospitable for them to provide a bottle of wine to welcome us, and two bottles of water were in the fridge.
The main train station is a short train ride away, like maybe 4 stops away, and the train that takes you to the main train station is about a two or three minute walk from the residence. Also there are stops nearby if you prefer to not walk much.
Again, we are happy we stayed there, and we highly recommend Massimo's place.