The apartment was absolutely great! It had a lot of space and was very clean (although the pots and pans were a bit dirty). As was said by other reviewers, the apartment is very dark because the windows are situated in an alley (daytime seemed like nighttime), but I personally thought this was forgivable since the lamps in the apartment were very good and I hardly ever spent a lot of time in the apartment. What I loved most about the apartment was the perfect location. It's located in a relatively quiet alley, but right in front of Quattro Canti, from where you can go to pretty much any hotspot in Palermo. Giuseppe was very responsive to any questions or requests, spoke English quite well, and gave me lots of recommendations on how to get to certain places and where to eat/go for a drink.
I'm planning on going back to Palermo very soon (as I absolutely loved it!) and definitely hope to stay at this apartment again!