It's not often to find an airbnb as comfortable as one's own home but Per's is just that. Peaceful neighborhood. Quiet building. Plenty of room to work if needed, relax of course after exploring oslo, and to just live your life 'as if' you were residing in Norway. If I needed a 1 month or longer stay in Oslo and Per was amendable to such I'd happily rebook for an extended period.
Mass transit is super easy in Norway and you have tram, bus, and metro options very close to the apartment. Lastly, the bed was super comfy which also made recovering from travel and exploring easier with some amazing sleep. There are a number of small grocers very close and a larger market a few minutes further plus a variety of restaurants also within easy walking distance.
The only thing to be aware of is that much like many buildings of this era in Europe there is no elevator so if you need porters everywhere you go this isn't the right apartment for you.
Highly recommended++++