Ḥanīfa when the other party is his father, grandfather, son, grandson, wife, slave, or mukātab (contracted slave).

Abū Yūsuf and Muḥammad, however, allow him to sell to any of those relatives at the going market price—except to his own slave or mukātab.

An agent entrusted with selling may, in Abū Ḥanīfa’s view, dispose of the goods for either a low or a high price. Abū Yūsuf and Muḥammad do not permit him to sell at a reduction that ordinary traders would not tolerate.

Conversely, an agent authorised to buy may conclude the purchase at the market price or at a modest premium that people customarily overlook, but he may not pay a surcharge beyond what appraisers would recognise; anything outside that range is impermissible.

If a selling agent stands surety for the buyer’s payment, the guarantee is void.

Should the principal commission him to sell a slave and he instead sells an undivided half, the sale is valid according to Abū Ḥanīfa. If he is told to buy a slave yet purchases only a half-share, the transaction is suspended; but once he acquires the remaining half, it becomes binding upon the principal.

If he is instructed to buy ten pounds of meat for one dirham and manages to buy twenty pounds for that same dirham—when ten pounds normally sell for one—then, according to Abū Ḥanīfa, the principal is bound for ten pounds at half a dirham. Abū Yūsuf and Muḥammad hold that the principal is bound for the entire twenty pounds.

When the agent is ordered to purchase a specific item, he may not buy it for himself. If he is authorised to buy an unspecified slave and does so, the slave belongs to the agent—unless he declares, “I intended it for the principal,” or he used the principal’s money.

An agent appointed for litigation is, according to Abū Ḥanīfa, Abū Yūsuf, and Muḥammad alike, also authorised to receive payment; and, in Abū Ḥanīfa’s view, an agent empowered to collect a debt automatically has authority to litigate over that debt.

If the litigation agent admits a liability against his principal before a judge, the admission is effective. According to Abū Ḥanīfa and Muḥammad, an admission made outside court does not bind the principal; it merely removes the agent from the dispute. Abū Yūsuf deems even an out-of-court admission binding.

When someone claims to be the absent creditor’s agent for collecting a debt and the debtor believes him, the debtor is instructed to pay him. If the creditor later appears and confirms the agency, all is well; otherwise, the debtor must pay the debt a second time and then recover the first payment from the purported agent, provided the money is still in his possession.

But if the claimant says, “I am the agent authorised to retrieve a deposit,” and the depositor believes him, the depositor is not ordered to hand it over.