The experience in Florence with Airbnb, in Giulia's house, was amazing. The apartment where we stayed was just as described if not better. When you get there it feels like you are in a real home.
I didn't meet Giulia, but we were in contact via phone and she was always super nice.
The apartment is not in the center, and it takes 10 minutes walking to get to the Duomo, and it is a pleasant walk. It is near Stazione Campo Marte, and there are buses that connect you to the main train station and other parts of the city. It is a very nice and quiet neighborhood.
I will stay there again when I'll be back to Florence!