You can access existing Invoices from a Client Account or from the Invoice List (Accounting > Invoices).
Invoice List
From the Invoice list, click any Invoice Number to open the corresponding Invoice overlay. The Invoice overlay will look like this:
The Client cannot be modified once the Invoice is generated. The Address, Tax Ref, Terms, and Payment Method are determined by the Client defaults. The fields in the right column can be modified.
You can modify any of the existing line items by clicking the pencil icon or the field you want to edit. If you're going to continue working on the Invoice, be sure to click Save on the line item when you're done:
To add additional services or products to the Invoice, click Add Line Item. If you're adding or editing a Product line item, be sure to choose your print options:
When you save each new line item, the totals at the bottom of the Invoice update.
The checkboxes at the bottom of the Invoice allow you to modify the Print and Email flags. You can also lock the Invoice or flag it for review.
Use the Memo field to record internal notes about the Invoice. The Client will not see these. If you need additional text to appear on the Invoice for a Client, you'll have to update the Invoice Description.
When you're finished editing, be sure to click Save at the bottom of the Invoice.