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Run the site report.
Enter the invoice period.
Amend any data which needs to be amended..
Raise or generate the invoices, which will send them to the customers and send you an accounts extract.
Run the site report again - if you invoiced everything this should show all uninvoiced amounts as 0.00.
The links above take you to the appropriate sections you need to perform the invoice run, however the site report can be found Outstanding Group.
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