Excellent location for exploring the historic district. Literally just a prayer away from the Cathedral and a short walk to the Normal Palace, Palatine Chapel, and San John Emeriti to the west. Same to the east to Quatri Canti, Fontana Pretoria, Sta Caterina, La Martorana, San Cataldo , Il Gesu, and San Domenico. Politeama (bus hub) and Central Train Station are just a 20 minute walk away.
I walked to his place from Politeama in the north and passed thru Porta Carini, the Capo market via narrow streets that I found to be quite charming and picturesque. Some parts of the neighborhood look a bit run down, but are very safe; and upon closer look, there is a lot of street art on the walls and structures (and yummy street food from cart vendors). The south side leads right to the arches of the Cathedral, and to the left are Piazza Vittoria on Corso Vittorio Emmanuel all the way to Porta Nuova to Piazza Independenzia.
To get to Marcello's place (and as disclosed before booking), you have to climb some steep stairs which reminded me of the song Stairway to Heaven because the loft space was boheminan, chic, and solidly cozy with those brick walls. The apartment has the essential appliances and a very strong wi-fi signal. I found it delightful that Marcello has anticipated a traveller's needs -- from providing maps, guides, tea, coffee, bottled water, to a spare bus ticket, an umbrella, toothpaste, even Q tips!
Marcello himself is quite the genial and accomodating host. We were communicating on What's App before I arrived and he provided me with the detailed information I needed to plan my daily schedules for my visit. He made some great suggestions for dinner and checked up on me each day to find out if there was anything I would need. He was more than just a host; I felt he was a friend.
Staying in Marcello's place was a huge factor in my enjoyment of my stay in Palermo. I would definitely stay there again, and highly recommend his place to others.