There is a building here not on the map. In the first photo, on the left, beside the apartment building. Appears disused. Seems to be part of the apartment block property though detached from the building itself. There is a play area, ostensible belonging to the apartment building, behind this other building - to the left, of screen, in the second photo.

via StreetComplete 54.1

Attached photo(s):
https://westnordost.de/p/182572.jpg
https://westnordost.de/p/182573.jpg