QB Issue Resolution:

https://www.thebalancesmb.com/do-i-charge-non-residents-t…

https://www.thebalancesmb.com/do-i-charge-non-residents-the-gst-hst-2948157

see the para titled But if they are not in Canada

Resolution for Issue 'Off customer part of customer payment against purchase' available: Yes (Solved).
Source: Intuit Community forum.

Off customer part of customer payment against purchase: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for Customer
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Error Recovery for Customer [Canada]
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