We had a great stay at Jocelyn/Silvio's place. Checking in and out was very easy and they were very responsive whenever we had a question. The location was great; there are plenty of bars and restaurants in the neighborhood and walking to some of the major sights like Sacre Couer, Notre Dame, and Eiffel Tower is not too bad (maximum one hour).
The space was quite small and was not particularly clean. Some of the dishes in the cabinet were still wet and/or dirty and there was dirt and hair on the floor. The mattress sagged in the middle and it gave us issues sleeping. The wine key in the kitchen was broken, though we managed to get our wine bottle open with some force.
Overall, we had a great time in Paris and enjoyed our stay. There are definitely some personal touches they could give the apartment, but it was a good deal in such an expensive city.