Karen's place is conveniently located 7 minutes from a bus to the city center, and is also walking distance to the main attractions of Zurich if you don't mind slightly longer walks. Karen was very accommodating with our requests and had clear communication the entire time. The room is quite big and can definitely host 2-4 people. For future guests just be wary that there is no elevator access to the apartment room which is two flights of stairs to climb with your luggage.