I am looking for a 2-bedroom apartment suitable for a couple and their two children (ages 4 and 5)

I am looking for an apartment for my brother and his family. I currently work in Oslo, but my brother will be starting his studies at University of Stavanger this August. The apartment will be for a family of four—two adults and their children, aged 4 and 5 (who, for the most part, behave well!). They are responsible, down-to-earth individuals with no pets, and they do not smoke or host parties. We are hoping to find a comfortable, quiet place where they can settle in and feel at home. One more thing to note is that he is an international student.