Abbey, USA: Great for a long-term stay
The flat and its location are great for a long-term stay. We lived in Girasole, Santo Spirito for almost a month while taking classes. The flat is comfortable, airy, and feels like home. The kitchen and bathroom are modestly sized for American standards, but sizeable for a Florentine flat. Santo Spirito is a great location because it is close to all of the touristy things, but you're not so in the middle of it that you're swimming in tourists. It was ~15 - 20 minutes to walk to the Santa Maria Novela train station, 10 minutes to Ponte Vecchio, 15 minutes to Il Duomo, etc. The neighborhood was safe--I felt fine as a woman walking alone late at night--and has amazing gelato (Gelateria La Carraia!) and food nearby. Finally, Diana and her team were always very professional, answered messages immediately, and were extremely responsive to all request/questions.