Mario is a friendly and flexible host (we arrived earlier than expected, but it was no problem), and he even greeted us with delicious homemade pastry.
The apartment is in a good central location, just a short walk from the Quattro Canti; however, be aware that it can get a bit loud due to its location right off a busy thoroughfare.
The kitchen space is a bit cramped and could use an update, but it served, and overall the apartment is a good value for a short Palermo stay.