This is really a lovely apartment in the middle of Palermo. The apartment itself has two good-sized bedrooms (each with A/C), a large living room/dining room/kitchen (combined room), two bathrooms (one large, one small) and, best of all, an ENORMOUS terrace.
We were there in October, lovely perfect Palermo weather, and spent every evening on the terrace which is quiet and calm away from the noise and clamor of via Maqueda. The terrace is private and large, with two separate seating areas, lighting, and enough chairs for a large group. Plants add to the wonderful feel of the terrace space. It's just really nice.
The apartment has been recently renovated, so everything works very well. Beds are comfortable and the rooms have the basics you'd expect, so very easy to use and live in. The kitchen is small and minimally equipped, so you can do some basic cooking, but it's not really designed for that.
Some things to be aware of: the bedrooms have balconies that look out on via Maqueda, which means that when via Maqueda is rowdy, there is noise in the bedrooms. The apartment is on the 3rd floor (4th American, with elevator) and that helps, but you will not be able to escape fully. The new windows help a lot with that, but if you are a light sleeper and there during good-weather season, you may want to bring earplugs to ensure a good sleep. The great thing is that the private terrace has the entire building between you and the street, so it is quiet and calm, an oasis in the middle of the city.
Of course the location is really fantastic for exploring Palermo; you are literally in the center of the city, equidistant between Teatro Massimo and the Quattro Canti. So if you are looking to visit all of the sights of this incredible city, you can't beat the location at all (as long as you don't mind a lot of people wandering around below your bedroom). Be aware that via Maqueda is a pedestrian zone, so no taxi can get you to the apartment very easily---your best dropoffs are Teatro Massimo or Piazza San Domenico.
The restaurants on via Maqueda are mostly tourist-oriented and both expensive and not very good, but there are multiple supermarkets in the area (check side streets as well) and because you're in the middle of Palermo, you can get to any of the best restaurants within a 5-15 minute walk.
I would definitely recommend this for 1 or 2 couples visiting Palermo who plan to eat most/all meals out, especially during good weather season when you can enjoy the terrace.
The host Peppe is super nice, super accessible, and very willing to offer advice and information about the apartment and the city.