This will cause him to realize that he needs to change his mindset in order to be successful.

Owning guns is a pain in the butt in CA, so I'm relatively light on the guns but have various bladed instruments staged about our home (that I own, obviously).The hoarding is the only thing you described that strikes me as unusual.This dude probably wants to do what is expected of him, which is not causing permanent damage to the property and pay his rent on time, in exchange for basically being left alone to quiet enjoyment of the unit.

Vacancies cause me anxiety, but bad tenants cause a lot more.

I agree with your comments that mortgage reits are vulnerable to rising interest rates especially if the financial reits are leveraged.Just as the energy sector (nat gas, crude oil, agriculture) are beaten down, I think that the Financial reits are trading 21% below book value and the reason for this is the rising interest rates are already priced in causing these reits to trade at such distressed levels.

Luckily I got him to pay the last  So I did my final inspection on the unit and deducted the damages and returned the remaining deposit.  

Any misstep could cause a serious delay in getting them out. 

Your burden of proof would require you to prove that any damages occurred during your ownership of the property which in my opinion would be impossible as you are not even sure when she left

My contractor ended up turning a 3 month project into over 7 months and it caused serious conflict with my roommates.

Does taking a HELOC cause any headaches for securing an additional loan from a bank on the balance? 

Rentals are indeed impulsive and delays cause people to get the apartments down the street instead of yours.