I stayed in Palermo two weeks in November to do an Italian language course.
The apartment is very well located and decorated very nicely with great love to tiny details. I loved the art nouveau files on the floor and the stucco at the ceiling. Very unique feeling!
It is in an old, typical Sicilian house but has been renovated recently. However, be aware that comfort cannot match that of a new building. The windows are old and hardly isolated. I had asked Stefania before booking her place whether it would be loud. She told me with closed windows it's not. Well, that's always relative I guess. To me it sounded as if the cars were driving through the living room... :/ And there is constant traffic in the street as the apartment is in the middle of the center. Moreover, there is a lovely café below the apartment which seems to be the place to be in town. Therefore there's always people waiting outside to be seated, chatting the Italian way. ;) However, it closes at 8.00pm. As I took Italian language lessons in the apartment all this noise was very inconvenient. Though if you are doing normal sightseeing and are just home to sleep you could be fine.
Also as the first person to stay there at colder temperatures and rain I was a bit unfortunate with some water coming into my bed room from / via the air condition which is used for heat as well, but this will be fixed now.
The TV didn't work which was also rather unfortunate for me because I wanted to use it for studying Italian.
Stefania was very friendly and helpful. She lives close by which made things easy and she even bought an extra heater (the air-con is in the living room) as I was cold.
So if you are a little flexible and appreciate the beauty and uniqueness of old buildings and are not studying at home I would still recommend the place. Just be aware it's noisy. ;)