I can’t say enough great things about this place. It’s walking distance to pretty much everything - we spent 6 days there with our 8 and 10 year old kids and took a single bus or taxi. Trevi fountain and the Pantheon are just couple of minutes away in different directions (perfect for strolling late at night or early in the morning to see (Rome without crowds), the Coliseum and Vatican are 20-30 minutes away.
The place itself is great because it has two large bedrooms on either side of the living room, so it provides a lot of privacy within the apartment.
It’s on a small pedestrian street, so there are restaurants literally under the window - I loved hearing people as I’m going to sleep but it might be a problem for those who need complete silence (if that’s the case, you probably need to stay away from city center). I felt very special pulling out my keys and sliding into a door right in the middle of all the tourist action :)
Lavinia is a great, communicative and accommodating host.