Haw. Rev. Stat. § 560:5-423: Sale, encumbrance, or other transaction involving conflict of interest.

Any transaction involving the conservatorship estate that is affected by a substantial conflict between the conservator's fiduciary and personal interests is voidable unless the transaction is expressly authorized by the court after notice to interested persons. A transaction affected by a substantial conflict between personal and fiduciary interests includes any sale, encumbrance, or other transaction involving the conservatorship estate entered into by the conservator, the spouse or reciprocal beneficiary, descendant, agent, or lawyer of a conservator, or a corporation or other enterprise in which the conservator has a substantial beneficial interest.