Thank you Ray for your detailed answer. I'm thinking this would work for us but we'd end up needing to build 1 price list per customer (depending on their tier of discounts afforded to them firstly on their individual discount and then on a global qty discount for each category/ or each product). If there was a way to give a customer 10%, 15% or 20% by assigning them to 1 of the 3 price lists and then let the global product qty discount apply when the savings supersede these lists, that's what I would be interested in achieving.

Pricelists with the Multiple Prices per Product configuration support this:

For a product like this:

And a pricelist like this:

Sales Orders would look like this:

If you have the need to build the percentage into the pricelist it self, you can then switch to Pricelists configured as Advanced price rules (discounts, formulas)

The pricelist would then look like this:

Same behavior on Sales Orders.