I call this one the jump scare building.
First time I’ve been inside, local youth (presumably) with at least one airsoft gun hid in a room upstairs. When I wanted to enter, completely unaware, they shot. The shock of that loud sound made me not only jump but run down the stairs, out of the building and over half of the complex like a scared deer. I felt like one. Today, I am grinning while I tell that story.