01
Ask what each quantity means
A roofing square describes area, while a pallet is a packaging unit and a piece count describes individual slates. Coverage depends on the specified dimensions and layout. Ask the supplier and installer to state the basis behind any area quantity, including the intended exposure. Do not assume every pallet of the same trade name contains an identical number of usable pieces.
02
Reconcile the documents
Compare the takeoff, quotation, order acknowledgment, and delivery paperwork using the same units. Keep accessory and spare quantities separate where that makes them easier to track. If a product size changes, have the installer recalculate rather than carrying over an old area-to-piece conversion. The goal is a transparent quantity trail from the roof design to the material received.