Lovely location, lovely apartment, lovely host, BUT…
Rome is HOT in the summer and this flat is not air conditioned. We had a hard time sleeping and when we returned each day, hot and sweaty from walking around the city, we could find no rest or relief in the apartment. We were very uncomfortable.
We stayed in several places in Italy, including one just two blocks away, that were comparable in age, architecture and price to this one, but they all had air conditioning and we were very comfortable.
I recommend you do not choose an accommodation in Rome that is not air conditioned. Or else visit in the winter.