What is the ruling on placing goods for sale with a shop owner, with the agreement that if he sells them, he is entitled to a certain amount?

The questioner:
Honorable Shaykh, may Allah grant you success, he says: What is the ruling on selling in this form, where a person places goods with a shop owner and says to him:

The Shaykh:
What is the ruling on it?

The questioner:
What is the ruling on selling in this form, which is that a person places goods with a shop owner and says to him: If you sell these goods, you are entitled to a certain amount.

The Shaykh:
There is nothing wrong with it, if he appoints him as his agent to sell them and gives him a share of the price as a commission, the broker’s fee, there is nothing wrong with it, yes.

The questioner:
And likewise, may Allah preserve you, if he specifies this matter and says: If you sell it, you are entitled to half of the profit in it, or a quarter.

The Shaykh:
This is not established, and where does the profit go? Does he take his effort for this? It is necessary to specify the effort, and if it is not specified, it reverts to custom.