The location was very nice, with a metro station and supermarket around the corner, and about 15-20 minutes from the center by foot. Also a relatively nice route (always downhill!). The hostess Simona was extremely available and friendly. She came to pick us up at the metro station at 23:30, to show us where to go, and also gave lots of information about how to reach different parts of the city etc.
And of course the apartment itself was beautiful, with very nice kitchen, bathroom, large bedrooms, and everything very clean. I would absolutely recommend it to anyone going to Napoli!