We stayed at Merethe's apartment - with 2 persons, in June - and we loved it. The apartment is perfect: it has a good layout, the bed and bathroom are comfortable, the kitchen is fully equipped, it has a big sunny balcony and it's situated in a nice neighbourhood.
From Oslo Central Station it's a 20 minutes walk to the apartment, or 12 minutes by tram (every 10? minutes). There're shared bikes at the tram stop as well.
The neighbourhood is quiet though lively. People meet each other in the inner garden. There two supermarkets around the corner and the cemetery is used as park to walk through towards city center. Nearby the tram stop and Kiwi supermarket there's the Santa Claus sculpture by Paul McCarthy, that we know from Rotterdam! We didn't check the Ekebergpark yet.
Communication with Merethe was very good. Best features of the apartment were the great balcony, good bed and nearby tram line. Would definitely recommend.