Firstly load the item you wish to apply up selling to, Check the use sub menus box and click on sub menus.



This will load the below screen. In which you need to name your sub menu and then click on department to link those times.



You have two ways to display the cost to the customer if you leave "Append cost and sales price of Items Sold in sub menus to base product?" unticked the customer bill will look like this:



Whereas if you tick "Append cost and sales price of Items Sold in sub menus to base product?"  the customer bill will look like this:



Once you have completed this selection hit save.


Now when a clerk sells the item they are presented with the below screen.