I visited Berlin on the 2 December 2014 and I decided to stay at Yvonne's. After 3 days at her place, I can tell that Yvonne is a very friendly and organized host! First of all, the room is very beautiful, due to her creative side. In the room you can find every possible information book or leaflet about Berlin and the room specifically. The area the room is located is very nice and will definitely get you in the mood to explore the city and learn about its history, since from the window you can see the Berlin wall.
Yvonne was very helpful whenever I had a question/needed information and at the same time really respectful of my privacy. She even allowed me to leave my stuff at her place for some extra hours, since I wanted to walk around the city during the day I was leaving.
One small tip: Ask Yvonne to give you the directions to her favorite Vietnamese restaurant!