I see this a lot and misinformation gets spread far too easily. I wanted to correct that in a short post.
The answer is to the question in the title is?
Fucking nothing you get a lawyer, invoke 5th amendment rights.
We have multiple success stories of using this method for receiving medium sized packs.
This happend to me before. If they come to your house. Step outside and ask to speak with them out there as they can get a bit nosey if you allow them i'm. Fortunately, yet unfortunately the vendor somehow messed up the address and the neighbor opened my mail and called the police. Opening mail that is not addressed to you is a federal offense. Case was dropped in a second. Also, don't incriminate yourself just keep quiet. They're not there to help you no matter what they say. They are there to bust you that's it.