This apartment served as a great base for our group of three for our week spent in Palermo. As described, the space is located upstairs on what in the US we would refer to as the third floor. The stairs are an easy walk up located along an interior courtyard. Inside the apartment is very spacious and well equipped. There are five shallow balconies in the space which is a wonderful amenity to have spread throughout the apartment. There are two bathrooms next to one another on the opposite side of the apartment from the bedrooms. There is a clothes washer (in bathroom) and TV (in living room) also in the home. The wifi worked well for our group the entire time we were there. For those who like to make coffee in the apartment there is a Dolce Gusto machine which takes capsules you can get at the nearby Lidl store for like two euros for a pack of 18. The showers worked well and had good hot water supply, my advice would be to only use one at a time to keep the water temperature consistent. As others have noted, the noise from the traffic can be loud during busy traffic times of day. I travel with a white noise machine and it worked well for this purpose.
There are numerous places in the immediate area (very close to train and bus station) and quattro canti is an easy 10 minute walk away with plenty of places to eat, drink, or shop along the way. One very close restaurant we enjoyed was Al Vecchio. There are numerous places close by to grab bottled water to replenish when needed and as mentioned Lidl is also nearby for more substantial grocery/snack shopping.
We had a great time in Palermo and this AirBnB helped make the experience a positive one. Innocenzo was very friendly and welcoming and super quick to respond. I would highly recommend him as a host.