Billit doesn't have a built-in function for work orders yet but you can easily create work orders by changing the layout of a quote, delivery note or order forrm.
Create a new corporate style for a quote, delivery note or order form and change the title and name of the layout template to 'Work order'.
Create three extra fields in the customer file: 'Time started', 'Time stopped' and 'construction site'. Now add these fields to the work order layout.
When you create a quote, delivery note or order form you can now choose the layout 'work order' to convert the document to a work order. You can fill in the start and end times in the customer file. Afterwards, you can easily convert the document to a real invoice by selecting it from the list and clicking the orange 'Invoice' button.