Quantity Discount : 24% to 32% off 5+ @ 24% : 3667.32 + 660.12 (18%) = 4327.44 10+ @ 28% : 3474.31 + 625.38 (18%) = 4099.69 15+ @ 32% : 3281.29 + 590.63 (18%) = 3871.92