Red ight , Green light
The red/green light is just an automated control, randomly selecting who is to be inspected, for the convenience of the inspectors. If you get the green you can still be stopped for inspection at the discretion on the ADUANA staff. Getting the green is not a 'pass' on inspection.
I arrived at the border 6 years ago, after dark maybe 10 PM. Largest UHaul trailer available, full sized pickup loaded. I looked like an Okie headed to Cali during the dust bowl. Had prepared a sort of inventory and prices of all the stuff I had, mostly used furniture and bicycles. Ignorent of procedure I did not stop to pay and got the green and started through. Frantic waving of an armed ADUANA agent got my attention and I stopped. He opened the trailer and a bunch of junk fell out. He was jumping up and down saying I needed an importer. I said where do I pay. He walked to the side of the truck, looked around and held out his hand behind him and said "under the wire, $100" I paid and drove through !! As I was pulling out of Sonoita a vehicle behind started flashing it's lights, oh crap stopped again. It was some US folk who told me the trailer door was partially open! Some stuff probably fell out but I just headed to my new home.:cruisin::cruisin: