Kryptronic Software Support Forum

Price reducing options are not present in K9.  They tended to be underused and misused in previous versions and when incorrectly set up created zero-priced offers.  The work-around is to set up your product offer with a zero base price and then use options to add to that price where needed.

You can find the product options in the admin panel here:
Dashboard / Store / Catalog / Options

You need to create the product option and associated selection items first, then return to the Dashboard / Store / Inventory / Inventory Items for the Product Offer and select the newly created Product Option from the Options tab.,