Firstly I will briefly introduce myself so that you know what type of traveller we are ;)
So... My friend Camille and myself have spent a week in Peter's appartment. We are both young students (22, 23) and were travelling and visiting the region.
The appartment was great for young travellers on budget. It is not very pretty, it is on the fifth floar without an elevator. But the location is great, 15min walk to Garibaldi, 10 to the shopping area and 5 to the harbour, where you can take the ferry.
On plazza san Domenico, where the appartment is (almost) you can find many restaurants, trattorias and bars.
The kitchen has no washmachine, not many plates, forks etc... You can cook but it is not made for big meals and good food.
Walter, the actual host, since Peter lives in the Netherlands, is extremly nice. He made all he could to make our stay enjoyable and gave us at arrival many tricks and tips on what to see and the places to be in the area. Also, he called the taxi for us the day before departure so that we were sure he understood right the street and the hours... Our italien is very "mezzo mezzo".
In a nut shell I would definitly recommend this accomodation for easy going travellers with not too high expectations. It could have been cleaner (shower not tiptop, ground not perfectly vacumed but acceptable), there could have been AC, and the street could be "safer" (we have not encounter any problems, but Walter told us to be very careful. In the area there are many pickpockets).
I would and so would my friend, definitly return in the appartment if we get the chance to return in Napoli.