Carrying distance is the real unit of work
Two rooms of identical size can take very different times to clean if one is at street level and the other is at the bottom of a tight stair. Every trip for water, every bag of waste and every piece of equipment costs time that has nothing to do with the surface being cleaned. Pricing these rooms per square metre produces a figure that cannot be delivered, and the crew ends up cutting the task list to fit.
Measuring the access properly is the fix. How many steps, how wide, is there a turn, is there lighting, is there a tap nearby or is water carried from the floor above. Those answers determine the time allowance far more than the room's dimensions do, and once they are recorded the quote is realistic and the attendance is deliverable. It also gives a relief crew a realistic idea of what they are walking into before they arrive.
