Uploading/Adding Private payments to CMS
Go to the Private Invoice you wish to mark as paid.
Click ADD Payment, changing the payment date if appropriate.
Go to REPORT and using the Invoice No, date as a filter, click apply.
This will bring up the billing to be marked paid to the provider, MARK PROVIDER PAID and enter the date you intend to pay the provider.
As long as you have the provider's GST information and payment percentage in their profile, this will then calculate the amount to be paid and you can create tax invoices in the usual way.