Nunzia's place is perfect for visiting the city and the surrounding area, since it is located in the very center, 2 minutes away from one of the most famous pizza places in the city - Sorbillo and the underground city, 15 minutes away from the port (so you can take a ferry to the islands around) and not too far from the central railway station.
The flat has all the necessities you need and Nunzia is very responsive and friendly. I would definitely recommend staying with her!