I can see how important it is to add the price rules feature in the QuickBooks Online (QBO) system outside the US, @MarkJames. 

For now, you'll need to change the amounts manually when creating the transactions. I'll let our Product Development Team know that you want this feature for Australia, too. They're still evaluating the feature for future product updates.

You can also send feedback to our product developers directly. Here's how:

1. Go to the Gear icon.
2. Select Feedback.
3. Type in your issue in the Share your feedback field.
4. Click Next.
    

Moreover, I'm including these articles to guide you managing your business transactions using QBO:

• Add product and service items to QuickBooks Online.
• Add a discount to an invoice or sales receipt in QuickBooks Online.
   

Please let me know if you have other concerns. I'm just around to help. Take care always.