Product breakdowns

Buy a case, sell the tins: open the case product's detail → "Break down into components", choose the date, how many cases to open, and the component products with quantities. Each component line has a value weight — its expected sale price (prefilled from market data when linked). The case's cost splits across components proportionally to qty × weight, conserved to the cent, so higher-value variants carry more of the cost.

Breakdowns appear in every affected product's working-figures history and can be undone as long as no component sales depend on them.