We loved our stay at this apartment. Irene was wonderful - so friendly and easy to communicate with from the start. When we arrived she sat down with us and gave us a helpful map and pointed out all the places we might need or want to visit. The apartment itself was absolutely lovely - the best part, of course, being the view. You simply can't beat this view of the Duomo. It was breathtaking. The location is perfect too - you're right in the center of the action, but on a quiet side street. The wifi worked well and was very fast, the apartment was very clean, and a great size (bedroom, kitchen, living room and bathroom).
You should note that the apartment is at the top of 3 steep flights of stairs, which is common in Europe, but be aware in case you're dragging a heavy suitcase - one of you will need some muscles!
Also because the bedroom faces the Duomo and gets a lot of sunlight, in the morning a little light creeps in through the shutters. We just hung a sheet over the window to make the room darker and that worked well for us. All in all, an amazing apartment in the best area of Florence with a wonderful host - we highly recommend it!