Is selling building materials in installments permissible or impermissible, after purchasing them from another merchant and entrusting the client to receive them gradually and directly from that merchant?

We understand that you bought building materials and did not take possession of them, and you appointed the buyer to take possession of them. This is a matter of scholarly disagreement, with most scholars prohibiting it, while some permit it if it is not a trick to engage in usury. We advise you to take possession of the materials yourself or appoint someone other than the buyer to take possession of them.