We stayed at the apartment as a family of four adults and thoroughly enjoyed our stay. It is beautifully furnished and very clean, with comfortable beds and a well-stocked kitchen.
The location is excellent, walking distance to just about everything you would want to see. There is a convenient taxi rank in the nearby Piazza for transport to train stations or the airport. The central location means it can be a little noisy at night times, however.
Being mostly vegan, we also appreciated that there were several eateries with vegan options nearby.
Overall we had a very positive experience staying at Andrea's place and would certainly look here for accommodation if we visit Florence again.