Regulations for Procurement of Real Property in Designated Areas by Entities Article 8

Any supplier responding to a solicitation of real property shall be either the owner of a real property or his or her entrusted agent. In the case of an agent, the agent shall, prior to award of contract, submit a notarized or certified letter of entrustment from the owner. However, for leased property where the subject of lease is of joint ownership, relevant laws or regulations shall apply.
中文原文 機關指定地區採購房地產作業辦法第8條
參加房地產應徵之廠商,應為房地產之所有權人或其委託代理人。
屬代理人者,應於決標前提出由所有權人出具且經公證或認證之委託書。
但屬租用且租用之標的為共有者,得依相關法令規定辦理。

English translation for reference only; the Chinese text prevails. Not legal advice.