Create a Variable From Item Property

If possible, it would be awesome, if it does not exist already, to create a variable out of an item property formula result. In my scenario I am calculating how many LY of wallcovering I need from the SF in one item. In another item I want to calculate installation cost but I want to grab the result from the material LY and us in my formula for the installation cost.

COST EACH FORMULA

Also, I see that I can use formulas in my [Cost Each] field which is great but I cannot seem to get the formula to work accurately. I have a variable called [WC Type]. If [WC Type] = "Wallcovering" then I want the value to be 20 else 6.5. I have tried numerous formula variations but the result remains 20 when I switch between [WC Type]. Formula I am using is below.

if([WC Type]="Wallcovering", 20, 6.5)