Overall we liked our stay in Fabrizio's apartment. It is spacious, clean, and good equipped. Fabrizio was an excellent host, very friendly, organized our spontaneous arrival (coming with the bus and metro from the Amalfi coast), and we could keep our luggage at his other apartment close to the train station after the check out time.
One reason we picked the apartment was the small balcony, to enjoy a breakfast at the open window. But the street in front of it is very loud and noisy so we couldn't really use it for that purpose. The bedroom on the other hand is to the inner yard and quiet.
The only real downside was the location. On the plus side it is close to the main station. But this comes at the cost that the neighborhood is not so nice, e.g. on our first walk towards the old city center we came in between a fist fight. The next time we would strongly prefer an apartment in the nicer (richer) part of Naples, located in the west.
Nevertheless, the apartment is well-equipped with everything you need - fresh towels, dishes, cutlery, good wifi. Thanks again!