I stayed at Magdalena's flat with my sister and my mother. It has a great location in a more quiet neighbourhood which still has some berlin-feel bars,cafes and restaurants around. it is also easy to reach all the main sites. The flat is spacious with a kitchen to have breakfast. However I would recommend it for just two people who sleep the double bed because the couch is not supercomfy.
Magdalena was also a friendly hostess who replied to questions quickly.