The spaces that belong to neither file
Lift lobbies on tenanted floors, fire stairs, back-of-house corridors, service risers, shared kitchens on multi-tenant floors and the goods lift landing are the usual suspects. Each is arguably common and arguably tenanted, and each is regularly cleaned by nobody because both parties assume the other's contractor attends. The condition of a fire stair in an otherwise well-maintained tower is the standard diagnostic. Loading dock corridors and the path between the goods lift and a tenancy door belong in the same category and are equally rarely assigned.
Resolving it requires someone to walk the boundary rather than reading two scopes. Twenty minutes with both documents and a floor plan will find the gaps, and they can then be assigned to one side or the other. That exercise is worth repeating whenever a tenancy changes, because a floor reconfiguration or a new demise line moves the boundary without anyone updating either scope.
