We stayed at Nina's lovely flat for two nights. There were five of us - myself, my husband and our three kids, and Nina was able to accommodate us all in the one main room. There are a lot of stairs to go up to get to the flat, but it is lovely once you get there! Nina was a great host - great communication before we arrived, the key was left exactly where she said, and she even left us a surprise box of cereal bars which were perfect for breakfast on our first day as we arrived in the middle of the night and tumbled straight into bed without thinking ahead to what we would feed the kids when we woke up!
I can't really comment on the location in terms of getting to the centre of Zurich as we were visiting friends who lived not too far away and who picked us up each day so we didn't use public transport. We did have a wander around the main shopping street near Nina's flat - several supermarkets, cafes and small shops. Thank you Nina!