Overall the stay was okay. A few things we noticed:
The kitchen has the bare minimum of necessary utensils and ingredients. Nothing bad.
There were only two main blankets for the beds and a small blanket for the couch. This was a little problematic since the apartment is quite cold in general. As well, no extra pillows were provided either, so plan ahead if needed. There was more enough cabinet space to store all of our clothes which was nice.
The shower door in the bathroom was broken when we arrived, but I fixed it well enough for our use. Only two towels were provided as well... this could have been okay if there had been a dryer. No gels were provided either, but there was enough toilet paper for several days.
The apartment was quite clean, so this was not an issue. However I must note that the WiFi was exceptionally bad. I discussed this with the host and he informed me it was a building wide issue, but this persisted our whole stay.
The location is great, it's in Karlin.