Unable to answer "Do you need to pay to enter here?" – Museum Huelsmann (Weiße Villa) (Museum) – osm.org/node/12321245680 via StreetComplete 59.3:

Wird nicht mehr als Museumsgebäude benutzt.

"Briefkasten nicht mehr vorhanden."
The place has gone or never existed. A user of Organic Maps application has reported that the POI was visible on the map (see snapshot date below), but was not found on the ground.
OSM snapshot date: 2025-02-27T10:33:49Z
POI name: Viktoriastraße 51, 33602 Bielefeld
POI types: amenity-post_box
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