In determining whether compensating tax is owed, the purchaser may rely on the seller's invoice or other written billing or contract documentation that indicates that the seller has charged the gross receipts tax or has included the tax in the amount billed (whether by name or indicating that taxes for the state of New Mexico were charged or included). Under Section 7-9-6 NMSA 1978, the seller need not state the amount of tax charged or paid.
N.M. Admin. Code § 3.2.10.24