Abstract
This example is focused in those kind of products for bulk selling, for example, vinyls, curtains, bricks, tiling, seeds, etc.

You can configure a base price for that products, and then, depending of the options chosen by the customer you can modify Final Weight of the product, just before adding to the cart.

Configuring Shipping
This kind of products should use a weight based shipping so activate it in Extensions > Shipping > Weight Based Shipping.
There you can set up different ranges of weights and prices, that will be used by OC to calculate final costs, given the final weight calculated by CFO.

Read more about Price, Quantity, Value, Weight, Points…

Dummy Demo
This is only a dummy demo, it’s not calculating any real thing, as you see the price is set by code to 8, and the final weight is entered by the customer in option_id {19}.

The point is to see how the product’s weight is changed on-the-fly and see how the cart is showing that changes.

//
// Change de Weight
$FinalWeight = {19V};

//
// Dummy price
$FinalPrice = 8;

You can visit this demo in our Demo Store