I spent two nights with my girlfriend and everything was perfect. Super clean and cozy apartment including all the amenities, towels, washer detergent... Every little detail has been taken care of, from a perfect wifi connection to bookshelves full of tourist information and maps of Florence, Tuscany, and Italy.
Location is also perfect. 5 minute walk from the Cathedral and right in front of the market (that is certainly worth a visit). The street is usually quite noisy (even at night) but the window, despite being old, offers a perfect isolation.

At check in I was first received by Tomasso's mother, a super-friendly woman who explained everything to me in Italian. Later, Tomasso arrived and little additional explanation was required. Tomasso is an attentive and communicative guy. We did not need to call him but we are sure he would be there to offer a prompt response.

The rest, as advertised in the listing: low ceiling, functional bathroom, comfortable bed... What else would you need?
We would definitively stay there again.