The apartment is in an excellent location. The historic sites, train station and restaurants are all close enough to walk to. The supermarket and open-air market are very close. Florence was flooded with tourists during my stay, but this area attracts a few less of them. The apartment is small-I am not sure four adults would be comfortable here-but has nearly everything you need. It does not have an oven, but you can boil, fry and reheat items on the 'hub'. As others have noted, the stairs are steep and hauling luggage and/or other items, may be a challenge. Check-in was smooth and efficient, and Fabio contacted me to make sure everything went well.
Fabio was friendly and let me know several times that he was willing to help with any concerns or problems, but I did not have any.
I would definitely recommend this apartment for people visiting Florence. It is great for longer visits as the washing machine works well.