I stayed at Betty's apartment for a month and it was the perfect spot. Betty was an attentive host, always checking in with suggestions of fun things to do around town and was quick to respond if I had a question. The location is perfect. Two blocks from the Duomo and close to everything. You literally cannot get lost because all you have to do is find the Duomo. The apartment was well appointed and I had everything I needed. You can hear the street noise enough to feel a part of the experience, but are removed enough from it to not be annoyed by the noise.
As the description notes, it is a fourth floor apartment (what Americans consider 5th floor). The stairs are narrow and steep. If you are out of shape or have bad knees, this isn't the spot for you.
As you can see from the photos, the bathroom is rather skinny and the shower is a typical tiny European shower. If you have long legs, it might be difficult to use the bathroom.