The room (appartment) was as i expected it from the photos on Airbnb. You can really see San Pietro from the kitchen's balcony! Nice.
It was a quiet area. I had no problem finding sleep. I felt comfortable in my room and bathroom. They were clean.
The breakfast was good compared to italian breakfast habits (Espressomachine with Capsules, Instant Coffee, Toast, Marmalade, Cornflakes, Milk, Butter, a fridge incl. freezer that you can use for your own stuff). If you are from Germany and expect a german breakfast: Forget it! But it's the same all over italy. Different countries - different (breakfast) habits!
When you arrive by Metro (Station "Ottaviano") you will have to walk approx. 15 min to get there. On that way you will meet thousands of tourists and you will cross the famous San Pietro place of the vatican. I saw the pope when i arrived on a sunday! From San Pietro to the Bnb it takes you not more than 5 minutes (walking).
But you can also take the bus number "64" from Termini in direction San Pietro to get there. One station is located directly in the street. 1 Minute walking distance from the Bnb. The bus will probably be totally crowded because it's a tourist line that passes all the important areas.

Contact with Elvio was absolutely easy and relaxed. He is answering immediately to airbnb messages. He speaks english fluently.

My experiences were positive. Thumbs up for Elvio and his BnB!
It was a pleasure.