‘Aqd al-Istisnaa’ (contract to have something made or done)
Question

                What is ‘Aqd al-istisnaa’?
      What are the rulings and conditions governing it?
Praise be to Allah.‘Aqd al-istisnaa’ – which is a contract that applies both to the
        labour and the product itself – is binding on both parties when it is drawn up in
        accordance with certain conditions.
      The following conditions apply to ‘Aqd al-istisnaa’:
Clear statement of the type, amount and required features of the work to
        be done or product to be made.

Specification of the time frame involved.

In ‘Aqd al-istisnaa’ it is permissible to delay paying
        the full price, or it may be paid in installments at specific times over a limited period.

It is permissible for ‘Aqd al-Istisnaa’ to include a
        penalty clause stating what the two parties have agreed on, so long as there are no
        circumstances beyond their control. And Allâh knows best.