I would like to offer volume discounts across ALL products in the range. We will offer 3 variants per product: bottle, 6pack, 12pack. I would like 10% discount to apply to purchase of 12 bottles or more across ALL products regardless of how the 12 bottles are put together e.g. 2 x 6packs, 12 individual bottles, 6 x bottles plus 6 pack etc etc etc.
What is the most efficient way to manage this please?