Communication with oben went great, he responds fast and friendly. Our trains were delayed so we arrived at the appartment pretty late, yet Oben's friend waited for us to let us in (which we thought was very kind seeing it was near midnight). We basically needed a place to sleep from which we could explore berlin, this is also what we got for a low price. However, if you have a high standard of comfort or if you intend to spend your holiday inside an appartment it might not be your thing, for it is not very luxurious. The bus and the metro were near the appartment and we basically spent our days in the beautiful city of berlin only to come back late at night, so for us it was fine.
Thank you Oben!