N.M. Stat. § 66-3-126
Casual sales; registration; penalty.
A. Unless a person is a motor vehicle dealer or the holder of a security interest filed
pursuant to Section 66-3-201 NMSA 1978, before the person attempts to sell a used
motor vehicle, the person shall legally possess the title to the used motor vehicle.
B. Any person who violates any provision of this section is guilty of a misdemeanor
and shall be punished by a fine of three hundred dollars ($300) or by imprisonment for
not less than thirty days or both.