First the good: The location is great, close to the train station and a short walk to everything in Florence you need to see. The room was nice and clean with its own kettle, microwave and fridge.
However, as everyone else mentioned, this room is loud. I am a heavy sleeper and we went into the room expecting it to be loud like all the reviews say, but it was shocking how loud it was. The room faces a busy street with a large window that is very old and only single pane. Right now it basically sounds like there is no window. If the owner replaced the windows with even the cheapest double pane windows (like almost ever other place we have seen in Europe) it would be 100x better (and would save on heating costs in the winter...). Also the breakfast is very minimal and a bit inconsistent. Croissants and toast crackers were replaced daily but the jams and honey and coffee were not some days (had no jams or honey the first morning at all).
Overall a decent deal, I'd consider it again but I'd also look at other options before booking.