This is a great place to stay. It is very close to the metro, which will take you to the city centre in no time. It's only 10 minutes by metro to Termini Station. The surrounding area offers restaurants and a supermarket very closeby. Serena helped us by sending eating/drinking recommendations and tips for public transport.
It felt a bit weird that Serena's cleaning lady "welcomed" is into the apartment. She opened the door, hurried us in and said some things in very fast Italian, then she was gone.
The apartment itself is great. Spotlessly clean. Large bed. If you're planning on cooking yourself, then you may find the kitchen quite unequipped. We only dined out, so this wasn't a problem for us.
On three of the four nights we stayed here, the neighbours were quite loud until around midnight. If I were a light sleeper, I wouldn't want to stay here.
Overall, we felt quite at home at this apartment and had a great time staying there. Thank you, Serena.