Good location, not exactly the city centre, but quite close to both the train station and the central streets (like 10 minutes walk). The neighbourhood is a little bit (only a little bit!) scary, but once you get used to Palermo itself you'll find it more or less average, or actually above the average :) And the view from the balcony is splendid!
Everything is in a walking distance: there are smalls shops, a "Lild" store, fast-food places, some restaurants. The city centre is maybe 10 to 15 minutes away depending on where you want to go.
The host was very, very welcoming and helpful and even saved my day once :)
Inside the apartment you'll find all the things you need to have a good stay with your friends, that's assured.