Even though we never met him, Nicola was a very accommodating host, quick to reply and offer suggestions when requested. The flat is compact but practical, with an excellent (and silent) air conditioning unit; the terrace is glorious, and really where you want to be.
The neighbourhood is quiet (at least at the end of August), not full of tourists but with plenty of good restaurants (check Nicola's recommendations; some are closed in August), friendly Indian-run delis as well as large supermarkets. It's a short metro ride to the centre and a pleasant walk to Via Appia Antica or Terme di Caracalla.
Highly recommended if you don't need or want to be in the thick of things.