We had a great stay at his property. It was well appointed with many amenities, including a coffee maker and several plug adapters that came in handy. Everything we needed, and a bit more, was here.
Although situated in a busy, louder part of Trastevere, with the patio doors closed, it was very quiet at night. The back terrace is small but a great place to have your morning coffee. Location-wise, it is very hard to beat- there are more restaurants in the 3-block vicinity than I could ever count, all we tried were very good. A taxi can usually be found nearby at Plaza Trilussa taxi stand, even at 6am (when we had early tours to meet).
The only caveats I would include are for guests who might have some mobility issues: The apartment is on the top floor, so there are 50+ steps to get to it; and the second bed is in a loft area accessible only by short (5-7 steps) but steep stairs that might be hard to navigate at night in the dark (although there is a right side (coming down) handrail on the wall). In addition, the headroom in the loft maxes out at about 5'8", so taller guest might have to do some extra stooping.
Otherwise, we were very pleased. Fabio arranged for a car to pick us up a the airport for $50E, which is about the standard taxi rate, and he was very helpful and responsive when I stupidly locked our keys in the apartment (be careful, that front door locks behind you automatically when closed, so make sure you always have your keys on you, not left behind on the kitchen table, like me.) Thank you! Ciao!