How do I create an invoice for a one off item?
Select your client
Click on Create -> Invoice
Using the blue checkboxes, untick all appointments/expenses (if there are any to invoice)
Click on Add New Expense:

Specify the details of the expense and click Save Expense:

You will be taken back to the Create Invoice screen, where the new one off expense item will automatically be ticked for you
Click on the green Generate Invoice button and follow the normal invoicing procedure from here.
Click on Create -> Invoice
Using the blue checkboxes, untick all appointments/expenses (if there are any to invoice)
Click on Add New Expense:

Specify the details of the expense and click Save Expense:

You will be taken back to the Create Invoice screen, where the new one off expense item will automatically be ticked for you
Click on the green Generate Invoice button and follow the normal invoicing procedure from here.
Updated on: 31/01/2023
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