I stayed at Marcel's place for just over a month and had a fantastic stay there.
The location is perfect for getting to nearly anywhere in Berlin and there's a metro stop less than 150 metres from the apartment.
The room itself was great and bigger than expected.
Everything was provided i.e. Linen/washing up utilities etc.
Wifi was fast.
Marcel was very easy to contact and overall I had one of my most pleasant Airbnb stays.
Would definitely recommend.