return order.quantity * order.itemPrice -
      Math.max(0, order.quantity - 500) * order.itemPrice * 0.05 +
      Math.min(order.quantity * order.itemPrice * 0.1, 100);

    const basePrice = order.quantity * order.itemPrice;
    const quantityDiscount = Math.max(0, order.quantity - 500) * order.itemPrice * 0.05;
    const shipping = Math.min(basePrice * 0.1, 100);
    return basePrice - quantityDiscount + shipping;