On the "add to cart" page, I let the user enter "Width" & "Length" to calculate the number of Square Foot as the quantity which works fine with a JS function. Now my client wants to add an "overhead" price to the product based on the selected variations. Is there a way, either an "hidden field" in the form OR a hook in the module where I can put the amount to add to the line item ? Or any other best idea is appreciated as well ! I'm on Craft Commerce 4.
You would need to change the price of the line item based on the option data sent in.