Layer	Document	When it is agreed
1	Master Services & Licence Terms	Once, on your first Schedule.
2	Modules — equipment use, purchase, rental, campaign	Never separately. A Module applies only where your Schedule ticks that capital route.
3	Installation Schedule	Per site. Scope, dates and amounts.

If you are buying a service and not renting a machine, you never read the rental obligations — they live in a Module your Schedule does not invoke. That is the point of the structure.

• Committed baseline as the PO — the default, and the least friction for accounts payable.
• Blanket or not-to-exceed PO — invoice actual usage against a ceiling.
• Equalised monthly with an annual true-up — a flat number every month.
• Your PO number on every invoice. One consolidated invoice per PO per site.
• We onboard in your supplier portal — Ariba, Coupa or otherwise — and build the service entry sheet into the cycle.