When we order a commodity that will be delivered later, the seller asks for a down payment as a security that the buyer will not cancel the order halfway through the making of the product.

However, the buyer pays only a token amount as advance and does not want to pay full in case the seller runs away with the money, then the buyer's loss will be more.

This is a common and accepted practice in our country.

We've learnt in module 7 that one of the conditions of advance payment is that full payment should be made. However, in the audio lecture, it is mentioned that the payment "takes place in advance in full or partially or continually in installments".

I'm a bit confused here. Is this practice mentioned above halal or will it be regarded as selling a debt for a debt?

According to a fatwa by the Islamic Fiqh Council this varies according to the goods being bought. If the required goods require manufacture then the above arrangement will be valid. However, if the goods are not manufactured but are bought from the market then the transaction will be invalid.