[mothered]

A very well documented, formatted and elaborated guide.

The trouble shooting process Is an Integral part of the SE, and you've detailed It nicely. The only part I wouldn't recommend doing, Is the latter of the boxing method as per below.

Boxing is the art of sending packages in a way which makes it seem that it was tampered with. e.g. filling it with rocks, books.

On receipt of the package containing rocks or books, alarms bells will be raised. It's extremely unlikely that the person responsible for stealing the Item during transit, will go to the trouble of replacing It with rocks. Stating the obvious, dry Ice does the job.
That aside, excellent guide.