Before we go into the details on how to update a functions invoice in Xero. Few things that you'll need to know. 

There are two ways to send a functions invoice to Xero from DotGolf.

(1) Send an invoice from the Function booking (calendar event).

- When you send an invoice from the calendar event, any unbilled items paid thru Functions Account (payment type) for the same customer will be consolidated on this invoice. 

For example on the day of the function, the customer had a bar tab of $23.50 and was paid thru using Functions Account. 

This bar tab will be included in the functions invoice if you are going to generate an invoice from the calendar event as shown below.

(2) Send an invoice for an unbilled customers page.

- Orders from POS that are paid thru Functions Account (payment type) appear on this page.

Note:

The system will be posting 1 Manual Journal per function invoice for GST adjustments. GST adjustments is required to offset the GST applied at the Point of Sale, so we don't double charge the GST.

Please refer to this article GST Adjustments on the function invoice.

General guidelines when updating a functions invoice in Xero

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Things to note when updating a functions invoice:

• Do not adjust any lines that already exist on the invoice. This is because a GST manual journal has been calculated based on these lines. If you change these existing lines, you would need to change the journal – not recommended.
• Instead – when needing to add/remove/change anything, we recommend you add a new line item on the invoice. 
• Either make the new line a positive qty or a negative qty (depending on what you are changing), and apply GST to the line. This way, additional lines have their own GST applied, and you do not need to worry about the original lines on the invoice, and the manual journal linked to these lines.

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We will be using the function invoice below as a sample

Scenario 1 - Adding new items

If you need to add items on the invoice, just add a new line item, encode it to the right account code and ensure GST is applied.

- Save your changes to update the invoice.

Scenario 2 - An adjustment needs to be made to a functions invoice for a Burgers & Chips sale having a total of $504.00

• Sale is composed of Burgers & Chips x 36 ($14.00 each) = $504.00
• But actually there were only 32 sold for a total of $448.00 so an adjustment needs to be done on the invoice.
• To make the adjustment from 36 to 32 (of Burgers & Chips), perform the following steps
  • Add new line item set the following on the new line item
    • Quantity to 4
    • Unit Price to -14.00 (negative value)
    • Code to Functions Clearing account (same account code as the original item)
    • Apply GST on the line item
•  Save your changes.

The updated invoice should now look like below.

• Review and approve when ready.

Applying payments on a function invoice

Please refer to Applying payments to a function invoice for details.