I would not converse with tenant in any format, as things could end up in court, if he declines to leave and has to be evicted etc. also don't confront in person, you said he is MMA fighter, good rules to live by include : Never get involved in a land war in Asia , and never anger a man with Cauliflower ears.

Bells ringing and whistles blasting.

Hey Earl, I sent you the link for the book's bonus.

I'd prefer not to give an entry code to lots of different delivery drivers if possible.In this position I'd wait until packages actually started getting stolen before doing anything, or maybe I'd get a Ring doorbell or camera. 

Fell free to give a ring if you wish- I will just give you the facts, no pressure.

Spend some of that money on a ring, and I would say you'll get amazing ROI.

They are allowable per code here but are generally looked at as temporary solutions and to be honest you can get a ring crimper for the price of about 4 or 5 press on fittings... thus cheaper and more durable/leak free to go the crimp ring route..

If you have advice about how to improve my process I’m all ears… 

You are talking to the Rolex wearin', diamond ring wearin', kiss stealin', wealin' dealin', limosine ridin', jet flyin' son of a gun, and I'm having a hard time holding these alligators down.

Hi John,I am getting a Ring Camera installed (lesson learned there).