The law in plain English
Return deadline
Under N.M. Stat. Section 47-8-18, the deposit response usually has to be sent within 30 days of the move-out timeline described by the state rule.
Required notice
New Mexico generally caps the deposit at 1 month's rent on leases shorter than 1 year, with no statewide cap on longer leases, and the landlord usually has 30 days to send the refund and itemized statement.
This dispute type
Once the New Mexico deadline passes, the dispute stops being only about the deductions and becomes a deadline-compliance problem too. A landlord may still argue damage existed, but N.M. Stat. § 47-8-18 sets the clock for returning the balance and explaining any amount withheld.
Penalty leverage
If the withholding was wrongful or in bad faith, the exposure allowed under the statute is: Landlord forfeits the right to retain any portion and forfeits counterclaim rights; bad faith adds $250 civil penalty, plus court costs and attorney's fees