i'm working with the travel agency. So it has expenses related to hotel stays, airlines tickets, certain tour tickets, car rentals for tourists,etc. Would they be under Cost of goods sold or Client Expenses?
COGS is based on inventory sales when you file taxes
I would create an expense account called Cost of Sales (COS) and use that. If you want it above the operating expenses as COGS is, create COS as a cogs type account, make the default COGS account inactive (I am not sure if QBO will allow that but worth a try)