We stayed a couple of days in Melissa's apartment, which felt like a home away from home.
Melissa took her time to help us where she could.
The apartment is about 5 minutes walk from a bus and tram stop. Line 8 took us to the center of the antique world in 10-20 minutes, for 1.5 euro per ticket (we didn't look into subscriptions).
If friens or family asked me where to stay in Rome, I'd answer: stay here, look no further.