Maria and her niece are extremely welcoming hosts. They are very reactive and communication has been easy throughout our stay.
They were very flexible regarding our check-in time; moreover, they let us leave our luggage in the flat on our last day so that we could enjoy Rome till the very last moment.
The apartment is very calm, very well decorated and pleasant to live in. A 30-35 minute walk will take you to any of the city's touristic areas. The Vatican is barely 10 minutes away.
Overall, a very good experience!