In regard to the postal stuff domestic is relatively safe. However, I did a sizable order years ago $2500 and the post office accidentally sent it to a business. They opened it, called the police and when I got home from work there was a note on my door I missed a delivery. Everything was blank and a number scribbled on the paper. I immediately got suspicious. I had a friend who was a Sargent at that police station, part of the order was for him. I called and explained he said don't call the number, take your gear to the gym and lock it in a locker. Clean up any email or anything and don't answer the door or unknown phone calls. If they happen to meet you there deny you even ordered a package. Refuse it no matter what they say. Don't sign shit. If they keep pushing you tell them they are harassing you. They have no way to tie it to you unless you accept it. Technically you not broken any laws. I was shitting bricks. He told me they will either toss it or take it and use it themselves and I wouldn't hear anything more. They didn't call or come back. Never heard a peep. Luckily I was moving out that weekend. So I moved my gear, moved out and ate the $2500 and never looked back.
Had a few get caught by customs. Nasty gram and an empty package. Nothing more. If anyone ever shows up asking you to sign. Dont