Price structures for invisible grilles differ for brands although it remains the most attractive aspect of modern construction. Stainless steel grilles besides the metal structures of construction for balconies are primary measures with square feet of the floor. Invisible grill for windows prices have different structures as it begin from approx. 280/sqft, extending to 600/sqft. Differences in prices are identifiable for stainless steel grills and metal grills for windows or balconies.