Custom pricing fails to populate correctly. We enter the SKU. Sometimes the correct price populates, sometimes a wrong price, sometimes no price. How to we address?

I understand how hard this has been, ldr514. 

Beforehand, may I ask if you are on the new invoice experience or the new layout for your sales transactions? 

In the meantime, we can verify if there are associated or entered End dates for the Price Rule. 

Let me show you how: 

1. Go to Settings and choose All Lists. 
2. Select Price Rules.
3. Locate the price rule in question and hit Edit. 
4. Modify the End date if necessary. 
5. Once done, click Update Rule and then Save and close. 

I'll add this article for additional info: Set price rules in QuickBooks Online.

Lastly, if you want to see your best sellers, what’s on hand, the cost of goods, and more, you can pull up reports to access your sales and inventory status. This way, you can get helpful insights into things you buy and sell and monitor inventory.  

I'm still all ears if you require more information about managing your custom pricing in QuickBooks Online.