FormulaPrice: Price by Formula

Sell what cannot be listed as variants. The shopper types a width and a length, picks a finish, uploads artwork — and the price updates as they type, from a formula you wrote. Start from a template: length, weight, area, whole boxes, volume, surface area. Each prices against the product's own price, so $20 on the variant means $20 per metre. The price is not taken from the page: checkout recalculates it from the shopper's own measurements, so an edited page cannot change what anyone pays.