Hi, When an item is marked as lost, the status of this item change and Koha will use the a Default Replacement Cost. This price is without tax sadly because it's based on aqorders.unitprice. But we need the cost of this item with tax (which is the real price paid for it). Then, the price needed must be based on unitprice_tax_included. To do that, the prices in these two areas : items.replacementprice items.price must be based on : aqorders.unitprice_tax_included. Thanks you, Alexandre