Not too thorough, I only found
But through the years playing TDM there is a kind of default picture of what rooms and services different kinds of buildings should have.
For example:
Basic apartment: only one room (bed, chair and table or desk), shared loo in the hallway. For a meal the tenant has to go to the nearby inn, and to the nearby public bathhouse for washing up (can't remember having ever seen a public bathhouse in any mission, though. Maybe most inns usually provide bathtub service as well?). Lighting only by fire.
Comprehensive apartment: sleeping room, private loo, heated living/dining room, serviced apartment kitchen. Lighting mostly by fire.
Luxury apartment: multiple sleeping rooms, private loo, bathroom with tub, living room, dining room, study/library room, serviced apartment kitchen. All rooms heated. Lighting mostly by electricity.
Manor: multiple sleeping rooms, loos, bathroom with tub, living room, dining room, study/library room, staff rooms, stairway, kitchen, storage room, garden, guards. All rooms for the residents heated and mostly lighted by electricity, staff rooms heated scarcely and lighted by fire.
Fixed doors are a both credible and lazy way to 'hide' several rooms, while keeping the mission straightforward. All kinds of 'missing' rooms can be behind those doors, provided that the building is big enough to contain them. But regarding the organic Bridgeport way of building, most adjacent buildings got heavily intertwined by the years.
Your CoS series makes clever use of fixed doors and these organic building blocks, which makes it both credible and straightforward, saving yourself and the player a lot of time.
Ah, I missed that sign. If it's only for orientation, maybe put it on the map then?
I have sore feet now, hehe!