Carlo met us outside the unit and was very accommodating. He took us by a local bar and coffee shop where we were able to get some additional recommendations of things to do in Florence. Our checkin process was excellent.
The apartment itself is fine and as advertised. As others have pointed out, the bar outside means there can be noise until 2am or so. This noise travels through the front door actually more than the windows, so it can be difficult to make silent. This didn't bother us though as we were so exhausted from busy days and are used to city noise.
The unit is small and rustic. We weren't concerned with the kitchen or seating as we just wanted a place to sleep in a central area which made it convenient. We lugged a big rolling bag from the train station and it wasn't too bad. It was pretty impressive Carlo managed to carry our 50 pound bag up the steep staircase even though we were perfectly capable of doing so (he insisted!).
Carlo was very kind to us, the apartment isn't luxurious and can be a bit noisy with the bar below, but it's a strong combination of location and value.