The apartment is great, well equipped with the things you need for a pleasant stay. It was really clean an ordered.
The apartment is quite close to the station where you can take the train, metro or bus, and in the zone there's a lot of markets.
Fabrizio is a great host. We met in Stazione di Napoli Centrale and went to the flat, where he gave me the details and told me about the city.
One thing to notice is that the apartment is in the 4th floor by stairs, so consider it if you're travelling with kids or elderly people.
I worked remotely those days and Internet's upload speed is not good, so probably you'll need to find some bar to work.