Thanks for joining us in the QuickBooks Community! My goal is to make sure you can enter the transactions you need into QuickBooks Online so you can manage your business's books. I'll point you in the right direction for entering your commission so it reflects in the PST Summary Report.
It sounds to me like you're referring to the PST Commission available in British Columbia. If that's the case, I recommend touching base with an accountant to determine the best way to record this transaction to reflect on your PST Summary report. There isn't a built-in feature or method for this kind of transaction, so having an accountant's touch is ideal for making sure things are being entered correctly.
QuickBooks Online's My Accountant tab gives you the option to invite an accountant you're already working with as a user to your account so they can work directly in your books. The Find a pro to help button gives you access to our database of QuickBooks-certified accountants near you. Feel free to check it out!