Is it possible to have a Receivables level rounding to full number?

Summary:

The company I'm working with uses a currency that doesn't usually use decimals and it's affecting some processes.

Content (required):

The company I'm working with uses a currency that doesn't usually use decimals and it's affecting some processes:

• Invoicing when the line level quantity is not a full number, need header level rounding, tried with the funcionality "header level rounding" at system options, but it's not working.
• Calculating earned discounts when creating receipts, the customer pays in full numbers, and the discount uses decimals, so usually there is an underpayment of the invoice.

Version (include the version you are using, if applicable):