I stayed at Riccardo's apartment with my girlfriend for three nights. Let me first tell you that Riccardo is a great host, not only did he meet us on the street after we got a bit lost (our fault to be honest) but also provided us with tips on public transport and other conveniences. There is a 24/7 supermarket right across the street and the place itself is less than 10 min walk from St. Peter's square and the Vatican. Metro stops are a bit a further but they are really walkable or you can just take a bus.
The apartment was clean, comfy and convenient. Located on the ground floor. Plenty of kitchenware if you're planning on cooking, fast WiFi and AC in every room. The bathroom is spacious and there is extra space to store the luggage right next to the bedroom.
We would definitely stay there again!