At the northwest corner of Addison and Wolcott, the storybook-like “mushroom house” appears to grow out of the sidewalk. Squat plaster walls, dotted with abstractly shaped windows, are capped with a steeply pitched shingled roof.

Von Hartz has become a sort of caretaker for Moelter’s mushroom, unchanged since the 60s and showing its age. “I think Charlie has very fond memories of being here,” he says, “and wants to see it kept intact.”