Nicola is a nice and helpful host, he responded quickly to messages and offered lots of info and tips. He even wrote us a small guide to reach the apartment, which is well located, 5 minutes away from the Furio Camillo Metro Station, in a quiet and picturesque neighbourhood, with cafes, restaurants and shops where you can eat and live like locals do. From here you can reach the main attractions in the city in less than 30 minutes. And another guide for Rome.
The very good price-quality ratio of this apartment is what you need for a few not very expensive days in Rome.
(Advice: during the cold season, if you don't like sleeping at night in about 18-19°C, you should tell ahead Nicola to warm up the place, for he has a remote control system that cannot be activated from within the apartment.)