ولا يصح السلم حتى يقبض رأس المال قبل أن يفارقه
Translation: Salam is not valid unless the seller receives the capital before the parties separate.
A fundamental salam requirement is possession of the entire advance capital in the contract session: the seller must receive the full agreed price before the parties separate. A promise to transfer later, an intention to pay or a small deposit does not satisfy this particular classical contract.
If the price is Rs 100,000 but the buyer pays Rs 20,000 now and the rest next week, the stipulated salam has not met this condition. A written receipt is not automatically a substitute for legally effective receipt of payment.