First of all, the location of this apartment is absolutely perfect. It is a block from the beautiful Arno river, and two blocks from the Uffizi Gallery. There are also tons of great restaurants within a 5-10 minute walk, and all of those beautiful, windy cobblestone streets. I stayed here for a month, and one of my favorite things to do was to just go out and walk around and kind of get lost, and this is a great place to do it from. Because the apartment is so near the river, the Oltrarno area on the other side is only a few minutes away too, and I enjoyed that area as much as the more celebrated side. There are parks where you can go up and see truly spectacular views of the city, plus lots of interesting bars and restaurants and artistan craftspeople.
As for the apartment itself, it was spotlessly clean and because it's on the top floor, it has a beautiful high ceiling, which made it feel nice and spacious. There's a big bedroom with a queen sized bed and a smaller room with 2 single beds. The kitchen and living areas are not the Ritz Carlton but they are very nice and there's also a small deck overlooking a quaint courtyard. The apartment is about 3 stories up. I personally liked walking up the stairs and liked being on the highest level.
The people who run the apartment were very helpful and attentive. I had a couple small issues (nothing major), and all I had to do was text them on WhatsApp and they always got back to me within a few minutes. If you are coming to this beautiful city, I honestly can't think of a better place to stay.