In order to do batch billing you need to setup your billing preferences. You can setup any number of billing preferences and then associate them with the appropriate action types. 
The billing preferences govern which invoice layout should be used and how the line items and headings are arranged.
To get to the billing preferences page, go to Admin > Billing > Billing Preferences.
You will then see the page in the screenshot below.
- Existing (if any) billing preferences will be displayed as in the list below. You can click on those to see how the billing preferences have been configured.
- You can create a new preference by clicking on this button.
Setting Billing Preferences for a Workflow
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2) Select your Default Billing Preference from the drop down list
3) Click 'Save'
