You can't beat the location. Just 2 blocks from the metro station and 3 blocks from the Colosseum. The pictures are accurate. There were 2 adults and 2 teenagers so we used the pull out couch in addition to the 2 bedrooms. Everything worked well. Frederic was responsive to questions and gave us great recommendations for restaurants that were not tourist oriented. He gave us suggestions on sights to see and even booked a taxi for us to get back to the airport.
The flat was one floor up but worked well. The only inconsistency was that the Airbnb write-up says there is breakfast daily but that was only coffee which you make yourself. That didn't really bother us, though, since that is all any of us typically eat in the morning and we were more interested in getting to the sites.
Overall a great place and a good host.