That was a great stay in Napoli! Communication with host went very well. There was quite big time window in which we could check-in, which was very useful, as we were not sure about exact time of arrival.
Maddalena was waiting for us in front of the building, gave us the tips how to get in and showed us the place. Apartment is located really high, luckily there's a lift, but note that during the day it costs 0.2€ (in the evening it's free). The good side of apartment being on last floor, is that the view is amazing - you can see a lot of domes and even a castle on the hill.
In the apartment there was everything we needed, to mention few - Wi-Fi, AC, water supply provided by host (some in the fridge, some in the rooms) and TV with Netflix and Youtube.
Location of the apartment was also very good - metro station is almost within sight range, it's close to both shore and the historical part of the city. Also next to the apartment there's a lot of cafes and very nice place "Ristorantino del Duomo" which is like cafe and store in one - with fresh prosciutto, mozarella etc.
If you plan to visit Napoli, I highly recommend staying at Maddalena's place!