And after the drop-off, the courier retains half of the bill w/ a serial # as proof that the delivery did occur. This prevents the buyer from later claiming "th

And after the drop-off, the courier retains half of the bill w/ a serial # as proof that the delivery did occur. This prevents the buyer from later claiming "the delivery never occurred, the courier must have stolen the drugs/contraband". If that claim is made, the courier can produce the note as proof of delivery.