Mari's place is close to Oslo Central. We arrived Oslo quite early but couldn't check in till 3pm. So just left our backpacks at the locker in the station( quite convenient. 70nok for a big locker and paid by CC). There are a couple of supermarkets nearby and liquor store inside the train station mall. Mari has a good binder with many Oslo information. The flat is quite tiny ( we knew but smaller than we expected)especially when you open the sofa bed. Lucky we only have two backpacks. Since tram is right on the street so can be noisy but she has many ear plugs in the bathroom. It is clean and Mari even left us some fruit and juice. Since we only stayed for two nights and had an early flight out so the location is perfect and we enjoy the walk around town without using the public transport too often.