My company usually send some of our parts (for production use) for outside service. We pay for the freight for both delivery the parts to the supplier and ship back to us once the service is done. So, are both freight-in and freight-out expenses for the parts considering as factory overhead or only the freight-in count as the factory overhead? This also situation also apply to our equipment maintenance and equipment rental. I just not sure are both way freight is factory overhead or not.

Thank you.