Observations of the exterior are dominant, except perhaps in rare cases when entering public spaces with a camera and notebook aren't met with looks of suspicion and the predicament of crossing various ethical boundaries (is it weird to be photographing a busy sunday afternoon at a public swimming pool? Er, yes it is).
When it comes to private spaces, one has to charm, bribe or barge their way onto the premises to attempt to record any fragment of an observation.
Like with anything private, it's protocol to receive a personal invitation to wander around, inevitably limiting the sphere of writing about the interior to professional writers, academics and those who generally know what they're talking about.
As an amateur writer who does not know what they're talking about and doesn't need an invitation to inspect their own flat - I thought I'd use this time in quarantine to exercise the skill of mapping interiors, and where better to start than the smallest and most politicised rooms of the lot: