I "shipped" some camping equipment to an address in PV. (DHL bill $900 CDN.) I was flying down the following week. Camping equip is tarrif free if you accompany it. The tariff bill from the Mexican customs broker--demanded an itemized list specifying country of origin--several items Australia, was 23,000 pesos and I had to pick it up at their warehouse at the Guadalajara airport.
It was pay tarrif or abandon shipment. Tried to return ship to Canada--no go. Abandoned equipment, repurchased in Canada, flew down with it as oversize baggage and "breezed" through PV airport explaining it was camping equipment.