Where to enter product cost (versus the sell price to customers)

-- url of the page with the problem -- : pumpkinvines.com/e
-- HikaShop version -- : 4.0.2
-- Joomla version -- : 3.9.1
-- PHP version -- : 7.1.22

Working on setting up a new online shop using HikaShop Business.
I would like to record the cost of an item (how much it costs ME) I do not want this information shown to customers. It would be for my own records.
Is there a way to do this?

Thanks
K