Great flat - exactly as described, clean and warm with everything you could need. I stayed with a friend one in each room and it was spacious for us. You could easily have 5 people (one on sofa bed) - living space would be a little crowded.
We didn't actully meet Barbara but she was incredibly accommodating - letting us check in early and check out later, with no extra charge. She left wonderful recommendations and texted us some extra ones. It was very easy to check in without Barbara there with the safety box.
The area is safe and quiet with a great bakery nearby also selling fresh pasta and a supermarket.
There was a small confusion about there being an empty extra cost for the second room - which wasn't clear from the page but Barbara kindly agreed to waive the fee in light of the lack of clarity.
Overall a great base to explore the city with everything you need. Would definitely return