Calculating COGS for a service company
I understand that COGS for a retail company is "begining inventory + purchases - end inventory = COGS."
But I have a company that provides services and products. Shouldn't the direct costs associated with providing our consulting/repair/maintenance/installation services be included in COGS? If so, what is the service industry COGS equivalent of "begining inventory, purchases, end inventory"? For example, if I have 10 full-time technicians, would then my "inventory" be 10 x (40hrs/wk) x (4.3wks/mo)? I need help getting on track with how COGS and services mix. Thank you.