Location Location Location!
This is the very center of ancient Rome, within walking distance from everywhere. We didn't use any kind of public transport once.
The apartment is fully renovated and was very pleasant to stay in.
Carmen and Harry made us very welcome, ordered a taxi from the airport and back, and gave recommendations for places to visit and local haunts to eat at, which is the proper way to eat in Rome.
The (arguably) best pizza in Rome is just 100m from the apartment, and is open until the middle of the night.
They even let us stay until the evening on the last day, so we didn't have to worry about our luggage.