In short
Neat place, exactly as in the pictures. Very clean, easy to find, transportation and stores withing 5 minute reach. One is quickly in the center, the hosts were very friendly so basically: it-was-amazing. 10/10 would recommend.
Accuracy
The pictures were already promising, but you never know how it really is. So we arrived in the evening, found the place easily, went inside and it was just as described. Very clean, everything was there (e.g. wifi, towels, hair dryer, dishes, ...).
Kitchen supplies are there, also a coffee maker and basic utilities. Since we don't drink (much) coffee, we didn't really need it, but if you do, you'd need to get coffee capsules since we only found a few. We didn't miss anything in the kitchen in general. I think they only had soap and no shampoo but we brought our own anyways, so that was alright as well.
Location
From the airport it takes roughly an hour to get to the apartment, but the transportation system is very accessible. Change to the subway once and walk around 5 minutes to the house. Very very easy. It takes around 30 minutes to get to the center via subway, but there was no problem whatsoever.
Communication
Sascha and Marina were always friendly and made sure that we felt welcome. They were quick to respond to any inquiries and answered every question we had :)
Check-in
This is very flexible which was convinient since we arrived late in the evening. The check-in-instructions were very clearly communicated, we had no trouble to find the apartment in the building, the key or entering the apartment. Easy going indeed.
Cleanliness
Super clean. The cleaninglady does a splendid job (is also very friendly, we encountered her when we left). Everything is neat, organised and generally very tidy.
Value
100%. I was surprised about the price, because the apartment seemed to be very well designed and modern. It turned out to be incredible, so all I can say really is thanks to the hosts, I recommend it without hesitation.