2 friends in Oslo for 2 nights. We had a great stay with Christer and can recommend. The room is small, but big enough to be comfortable for a couple of nights, and clean. Faces a courtyard, so quiet at night. There's a supermarket right around the corner, which is very convenient for snacks etc.
Make sure you go to the 8th floor roof terrace for the view! (NB: Norwegian shops stop selling beer after 8pm)