I am very happy with my stay at Martin's place. I was there for almost two months, so believe me when I say that Martin is a very social person, he is easy to get along with. I had no issues with him whatsoever, he is definitely a good host and person. You will have no problems staying at his place! The apartment is perfectly sized for two people, the kitchen is big and the living room has enough space. The apartment is clean, modern and cozy. The room you will be staying in is a normal sized guestroom, with storage for your clothes and other things. The room also has its own balcony. Regarding the location, there is public transport right outside the building that can take you anywhere in Oslo. There is also a grocery store right next to it. If you want to rent a room in Oslo, this is a good choice!