What are the permissible scopes for appointing an agent in marriage?

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The appointment of an agent in marriage is permissible absolutely (Mutlaq) or conditionally (Muqayyad). A conditional appointment is delegating the marriage to a specific man. An absolute appointment is delegating the marriage to whomever the guardian approves or whomever the agent desires. Ahmad, based on a narration from Abdullah, permitted an absolute delegation for a man appointing an agent for his sister or daughter, stating that if the agent finds someone satisfactory, his marriage of her is valid. This is evidenced by the report that an Arab man left his daughter with Umar ibn Al-Khattab, instructing him to marry her to a suitable match, even if it were for the price of his sandal strap. Umar married her to Uthman ibn Affan, and this action became widely known without any denial.