RICS Rules of Conduct and Global Professional Standards COI-1.1: Conflicts: no advice or representation with a conflict unless all affected give prior informed consent

No member or regulated firm may act for or advise a client where doing so entails a conflict of interest (party, own-interest or confidential-information conflict) or a significant risk of one, unless everyone who is or may be affected has given prior informed consent; consent may be sought only where going ahead serves everyone affected, is lawful, and will not stop the member or firm giving competent and diligent advice. Informed consent requires the party to show it understands that a conflict or significant risk exists, the material facts known, what the conflict is or may be, and that it may limit the ability to act fully in the client's interests.