The apartment of Mia and her family is situated in Østerbro which is a nice and quite part of town. It's close to Nørrebro (student quarter) and 20 minutes from the center by foot. I recommend to rent some bikes as almost every person in Copenhagen seems to use his/her bike and the streets are made for it!
The stay in Mias apartment made our time in Copenhagen very comfortable and nice as it's very cozy. Besides that we had nice talks to her and her boyfriend - very lovely and interesting people.