Stefano's place is a nice and cozy apartment, located on the top floor of a nice and quiet building. There is an elevator that takes you to the last floor, and then to reach the apartment, you need to walk up two flights of stairs (maybe just to consider if you are travelling with the elderly or the disabled). The place was very clean, comfortable and bright (exactly as in the photos), and the view is absolutely amazing! You will have access to two big balconies to enjoy day or night view of the St. Peters dome. The kitchen has almost everything you might need during your stay.
Location: The apartment is located in a privately-accessed alley, right in front of the Roma San Pietro train station (so consider that you might hear the trains' sound as they pass during the day, but closing the windows, it was okay and the sound didn't bother us that much). It is very easy to find the place, and is very well-connected to other parts of the city with trains or buses. Vatican church and museums are in 15-20 minutes walking distance. There is also a supermarket 2 minutes from the place, so very comfortable for grocery shopping.
We didn't meet Stefano in person, but his sister was waiting for us when we arrived, greeted us warmly and gave us some tips about the zone and places around. Overall, we enjoyed our stay in this place and if you are looking for a cozy bright place with a nice view, this is definitely the right choice!