The only negative thing was the double bed, because it was a combination of two small mattresses and we couldn't sleep.
Everything else was perfect,the decoration, the location of the house ( 10min away from the train station, pretty close to catacombs/restaurants and almost everthing) and last but not least Salvatore's hospitality and communication. Also he offered us to transfer us to the airport early in the morning (07:50) for the price of 25 EURO.
We had a great time at Napoli. We would definetely recomend staying at Salvatore's place (either 2 or 4 people)