Let me start by saying our experience in Rome was fantastic!
Unfortunately we did not meet the host in person (so we could not give her a hug), but she was very kind and more than helpful. Everything was arranged for us as promiced and even beyond.
The appartment is not big, but that was not a problem to us at all. There was enough room for two people. It is a cosy and convenient place to stay. One quibble that the ceiling is pretty low in the living room, so it might be a bit of a problem for tall people.
Streets of Trastevere are noisy at night. We had some concerns about it. Windows of the living room go out to the street, but bedroom is situated on the other side (it's windows open to the back yard). It is well isolated, so once the door is closed, you can hardly hear anything. We slept very well in a big and very comfortable bed and had no issues with noise so far.
The location is just amazing! It is in the heart of Trastevere next to Ponte Sisto.
The flat seemed very safe. There is an entrance door that is locked. Upstairs there is a middle door that is also locked. And for sure there is an entrance door to the apartment with a lock.
Long story short... when I go to Rome next time, this cosy attic will be on my wish list for sure.