What a great place! We absolutely LOVED the location (2 minutes from the Duomo and San Lorenzo; 15 minute walk from the train station). It was so convenient to major sites! The large rooftop terrace was AMAZING with its view of the Duomo and San Lorenzo. Sitting there with coffee and listening to the bells in the morning was a favorite thing for our group!
There was a lot of space in the bedrooms and living room, but the kitchen is tiny (though serviceable). Be prepared for a lot of stairs (as mentioned in the listing). They are pretty narrow and steep, but with sturdy handrails.
Bedrooms and bathrooms are on the 3rd floor entry level, with the kitchen and living room one level up (4th floor), and a small dining table a half-level up from there (I used it as my computer center; WiFi was pretty good and consistent there, while rather spotty in other parts if the apartment). The rooftop terrace was an additional half-level up (5th floor). We spent a lot of time up there!
The apartment entrance is on the 3rd floor (that's the 4th for Americans). The lift starts on the 1st floor after 16 stairs up from the ground floor. It is very tiny, barely fitting 2 people (or one plus luggage).
The beds were quite comfortable, with 3 singles in one room (with tiny en suite bathroom: shower was really too small to use) and 2 singles (or good-sized double) in the other. The main bathroom off the hallway was much larger, with a good-sized shower (plan on everyone using that one!).