This is a cute apartment in the Valle area of Oslo - so it's not central, but it's pretty close to Helsfyr, which is a subway station.
Parking was a little hard to find, but you can park in the circle, which is what Maria refers to as 'the street' (it's not a street per se, but a circle driveway for the entire condo complex).
Maria's apartment was well-decorated and cozy, but the bedroom was a bit small - the bed is arranged sideways in long room, so you have to climb over your partner to get out of the bed. The 'closet' randomly takes up about 1/3 of the room, so you don't feel like you can move around the bedroom at all.
The kitchen was nice and large, but the kitchen rug, and all the rugs, in the apartment slip and slide if aren't careful (rug pads would've been a nice safety feature).
The bathroom is also very small with a 'folding' shower, which means you have to assemble the shower when you want to take one. The washing machine is a mini-machine, but it does the job (no clothes dryer, like the rest of Europe). When you sit on the toilet you literally hit your knee/thigh on the sink, which is odd, considering there is a ton of room on the other side of the toilet.
Maria had a really sweet cat that we doted on during our visit. She also had very nice neighbors that let us into the apartment (Maria was away on vacation).
Overall, it was a nice stay in a cute apartment, but I would suggest having a car since it's a good 10-15 minute walk to Helsfyr.