Now you can sell size specific products tailored to the client's needs, carpets, flooring, wood merchants, metal suppliers, garden furniture makers, window companies, cloth manufacturers, in fact any product that involves cut goods, sold by dimension, length, width, height, surface, the list of uses for the CustomSize plugin is endless. CustomSIZE plugin and VirtueMart calculate the correct price for your customer, dynamically, based on the size they require. You can use a fixed standard price or use the price of a variant selection. You can use a fixed product price and add additonally a price per unit, or use the product price as unit price. You can also use predefine values displayed as dropdowns. The frontend layout is also overwriteable (radio buttons instead of dropdown for example).
Link to product: extensions.virtuemart.net/products/custom-size-detail