When invoicing, you have the option to add time and expenses. Remember that the option only appears after selecting a Client Name to invoice. Let's go through the steps for adding expenses to an invoice.
Add Expenses to Invoices
1. Click + Add time and expenses.
A window pops up showing unbilled time and expense entries for that client.
2. Mark the boxes for the entries you'd like to apply to the invoice.
3. Select Invoice Entries.
The invoice reloads with the items you added. Take note that the Expenses are labeled as such in the Service column.
From here, carry on with any other details needed before saving and sending the invoice.
For reference, here is a screenshot of how the invoice preview looks with Expenses.
Take Note: You cannot edit Expenses that have already been billed. You can, however, add more expense entries to an already sent but unpaid invoice.