Shelf, mirror and picture hanging in Markham keeps meeting the same wall: the three-storey townhouse stairwell. Cornell and the Highway 7 area are full of them, and that stair wall is often the largest uninterrupted surface in the whole house.
I treat it as one composition rather than a row of separate frames. Layout on paper first, tape on the wall next, drilling only once you have signed it off. Working above a staircase needs proper ladder footing, so nothing leans on the drywall and no tread gets scuffed on the way up.