When is the payment due for the golden bracelet for which I paid a down payment: Should I pay it before its completion, in installments, or upon receipt?

There is no objection to providing a down payment and paying for the bracelet in installments or in full. It is permissible to sell gold jewelry of the same type without requiring exact equivalence, with the excess value being attributed to the craftsmanship. However, it is preferable to pay the full price when the jeweler delivers the bracelet.