No exhaust fan, no window — ventilation arguments

Bathrooms need ventilation — a working exhaust fan or a window that opens. The fights happen in older buildings where neither exists and adding one means real construction money. What has your inspector accepted, what got cited, and what retrofit actually solved it for good?

This is the bathroom argument that never dies, because the building stock is older than the expectation. No fan, no window, and a resident who showers like they are steaming vegetables — moisture loses every time, and then it becomes a mold conversation in the Mold forum. Retrofits are real money, which is why the planning matters more than the panic. For those running pre-war buildings, what did you end up doing — retrofit fans through the wall, ductless units, or fighting the cite?