Alexandra's place was clean and comfortable. She was away on vacation so we mostly communicated with her neighbor, who was fantastic.
The only note I'd make is that the pull out bed is much better suited for 1 than 2. Only one side of it is really comfortable and it's a short bed not made for taller people.
The apartment is in a residential part of Berlin, and in a lovely neighborhood. Be prepared for a 30 min commute if you plan on going out to central bars.