Great place in the center of Naples, it's just 12 minute walk from Piazza Garibaldi/Central station, but still very quiet and away from traffic noise. The apartment is really the 5th floor - 102 stairway steps from the street level (no elevator available), recently renovated and well equipped.
Two rooms (both with AC), kitchen, bathroom and the massive terrace. Multiple smart-TV screens (Youtube/Netflix supported) and high-speed (100M/20M) internet is available. When the windows/doors are closed, guests can block the city center noises. To be noted, that some noises from the stairway can be heard in the living room (there's a gap under the entrance door). As all the windows/doors have blinds, it provides great protection from the sun/light too. The apartment has no ventilation, so air can be exchanged only by opening the windows. The bedroom bed is great, but the couch isn't very comfortable for sleeping - best experience is guaranteed for 2 visitors.
No washing machine for clothes, but there's a drying rack for clothes on the terrace.
Host is very helpful and waited us at the apartment. Special thanks for the suggestions and nearby information.
Nearest "average size" groceries store (IperCoop) is just 5 minute walk away, around the corner from Coop is very good Pizza/Grill place - Pizzeria Hermanos. I would say that the surrounding area nearby the apartment is pretty safe - no disturbing or homeless people were noticed nearby.
When You need a place for 2 people in center of Naples and rely on public transport (trains/metro) for day trips - Antonio's place is really a very good choice!