If you don't want to invoice customers for materials taken out of inventory and used in their jobs, you can still track the costs and changes in inventory. QuickBooks calculates the amount by which to reduce the value of your inventory and assigns this amount as an expense for the job.
To do this task
Go to the Vendors menu, choose Inventory Activities, and then click Adjust Quantity/Value on Hand.
Enter the job name in the Customer:Job field.
Enter an expense account in the Adjustment Account field.
In the Qty Difference field, enter a negative number for the quantity of each item used in this job.
Track and charge for inventory used in a job