You need 3 Groups for Curtains:
-Main fabric group: This will have all your fabrics and the script.
-Components: This will house all your fullness/heading styles as well as motors, lining, tracks, etc.
-Labour: This will have labour inventory only. You can have different labour charges for different fullness or other options, as well as labour for lining and the same script.
Create your Groups following the instructions in the Inventory Groups help page: Groups (Products)