An authority expressed in general terms, however broad, does not authorize an agent to act in the agent’s own name unless doing so is the usual course of business, to define the scope of the agent’s agency, or to do any act that a trustee is forbidden to do under chapters 59-09, 59-10, 59-11, 59-12, 59-13, 59-14, 59-15, 59-16, 59-17, 59-18, and 59-19.