You may wish to add items to your events that are needed to execute the event but aren't going to be billed for and shouldn't appear on the proposal, contract, any addendums, or invoices. To mark an item as unbillable (an internal-use-only item), simply check the Unbillable box when you add the item:
When you check Unbillable, the price field will be hidden (because you are not billing for these items), but you are still able to enter a cost, if needed. This ensures that the event's profit and loss is calculated accurately.
If you would like complete step-by-step instructions for adding items to your events, please see Add Items to Functions.