Near Repubblica station, across from ancient ruins. Away from the main tourist attractions, but we used metro and/or buses to get around so it was no issue at all. It was actually great to be next to Termini because that gave us more public transportation option and a landmark when we were lost on the Vespa. Great suggestions for restaurants and Vespa rental (thank you Simona! Dagnino was so good) Bedroom and living room is the same space; kitchen is behind a door and connected to the bathroom. Kitchen was well equipped and we ended up eating in most nights as we were tired.
We stayed for 11 days and would stay here again next time we're in Rome.