The location can't be better than this if you plan to visit places around Naples. The flat is located right between the main train station and the seaport (a short walking distance for both). This was very helpful to get to Pompeii, Capri, and the Amalfi Coast. It's also next to the Duomo Metro station, the Old Town, and the most famous pizzeria in Naples.
The apartment itself is spacious and clean, with everything that we needed, even with a washing machine if you need to do any laundry.
Sergio was also a great host, coming down personally to help us check in and shared good food places in the area with us.