At first I was a little concerned because our scheduled arrival date was coming and I still had not received a response from the host for about a week. I had to ask Airbnb to contact the host on by behalf, then I started receiving communication from the host. Besides this delayed communication, everything else is great.
The location is excellent and central. We walked to all the major sights except the Vatican where we took the metro. There are several local restaurants and bars around as well as a couple convenient stores. The flat is on the 3rd floor (but you press #2 in the elevator) and is very safe. You have the first key to get inside the building and a 2nd key to get into the apartment. The apartment itself is roomy but the shower is very tiny compared to American standard. There is no A/C but fans are provided. We were here in early June and it felt very comfortable inside with the window opened.
Overall, a great place to stay in Rome. We really enjoyed staying at Yolanda's place.