@nmballa 

Correct, but COGS should not be used with non-inventory items.  COGS is an expense account that is used to expense the cost of inventory items at the time they are sold.  If you report COGS, you need to file Form 1125-A with your tax return or complete the COGS section in Part III  of Schedule C on your 1040.  Either way, COGS is calculated using the beginning and ending (of the tax year) inventory values.  If you have no inventory, you should not have COGS.  Instead of using COGS, you can use another expense account like Cost of Sales or Materials and Supplies.