Fabrizio is an excellent host. He was very kind, gave us a lot of information and was always keen to help in any regard. He messaged us during our stay asking if we were doing okay and was also very flexible with the checkout. The apartment is very spacious (bigger than on photos) and has a small balcony, from which you can look over the city and even see Vesuvius on a clear day. It is rather well equipped overall, though maybe the cutlery could be better especially if you plan to cook. We were there in September and it was still getting pretty warm in the bedroom so we were sleeping with two fans running the whole night. The bed is very soft so if you are used to hard beds you might find it uncomfortable. It's two mattresses connected together.
One thing that must be mentioned is the shower. It takes an unusually long time to get hot water in the shower and then it doesn't last very long and you have to wait again. It might be frustrating for some, but maybe gas heating works like that in all of Naples. We preferred to wash our hair in the sink where warm water appeared faster and was more predictable.
The location is great, 5min to main station where you can get a train/metro to anywhere including Pompeii, Vesuvius, etc. Good restaurants and cafes nearby. Downtown is maybe a 20-25min walk. This was very convenient and we barely used the metro at all.
Overall, the place is very good for the price.