We had a great stay at the apartment! It is very beautiful, and we didn't want to leave.
The pictures are totally accurate. The view is perfect and the balcony is a great place to rest after a long day visiting the city.
The apartment is perfect for four people. It was very clean and tidy. The kitchen is well equipped and allows you to cook as much as you need. The bathroom is wide and well equipped too.
The street where the apartment resides is really recent (few years ago), and offers a beautiful walk, with multiples bars and restaurants. There is also a grocery store at few minutes away in the same street.
About Øystein, he is very reactive and helpful. He helped us the most he can and tried to make us have the nicest stay possible. We would recommend him and his apartment strongly if you have to stay in Oslo!