Absolutely loved Federico's apartment. The interior really is as unique as the photos show. The glass floor walkway in the upstairs balcony area leads to a large window that is the primary light source for the apartment. You can actually open the window to access a small rooftop ledge surrounded by the classic terra cotta rooftops that are a signature of Florence. One thing to watch out for is the large support beam near the bed upstairs. It's very easy to accidentally bump your head on it in the middle of the night so be careful ;)
The location of the apartment was even better than expected. It was extremely walkable to all the major sights in the city. We found that the Duomo and Palazzo Vecchio were only steps away in either direction and the Ponte Vecchio and Oltrano wasn't much further.
When we arrived Federico's business partner Costanza met us at the apartment. She provided us with a map on which she highlighted the major destinations and restaurant recommendations. Her advice was super helpful throughout the whole trip and she even followed it up with a thorough Airbnb message containing detailed descriptions of all her recommendations.
We loved it and would absolutely go back.