I stayed 14 days at Federica's place. It was really perfect.
The room is really spacious and all the apartment is very clean !
To visit the city you have a lot of transport just in front the building (bus, metro, tram), only 10 minutes from the duomo.
I don't saw Federica and his husband a lot but they were really kind and helpful with me :)
I recommend their apartment for sure !! :)