Istisna [font, alqalamreg, (استثنا)

It is a sale contract where a buyer orders a manufacturer or seller to produce or construct a specific item according to agreed specifications, price, and delivery time. It is commonly used for custom-made goods, large-scale manufacturing, and construction projects. When they reach a consensus, they enter in to an agreement. In this agreement, the customer can pay partially, or completely in advance or in installments for having the desired product manufactured.