N.M. Stat. § 45-5-423
A person who in good faith either assists a conservator or deals with him for value in any transaction other than those requiring a court order as provided in Section 5-408, is protected as if the conservator properly exercised the power. The fact that a person knowingly deals with a conservator does not alone require the person to inquire into the existence of a power or the propriety of its exercise, except that restrictions on powers of conservators which are endorsed on letters as provided in Section 5-426 [45-5-426 NMSA 1978] are effective as to third persons. A person is not bound to see to the proper application of estate assets paid or delivered to a conservator. The protection here expressed extends to instances in which some procedural irregularity or jurisdictional defect occurred in proceedings leading to the issuance of letters. The protection here expressed is in addition to that provided by comparable provisions of laws relating to commercial transactions and laws simplifying transfers of securities by fiduciaries.
NMS § 45-5-423