But $100 is far less than she would have been charged if she had called a fence repair company, and is a reasonable amount given that someone had to drive there, own the tools to make the repair, check the measurements, cut if necessary, install the new pickets in a seamless manner, then pack up all their equipment and leave. 

One was a vending machine company.

Don't forget to check for power on equipment in the basement or common areas.

Assuming it was a blue Supra box, police can't even break into those things without major equipment (ask me how i know.)

Part of your plan for being a Landlord (Investor) should entail, office equipment, phone, desks, computers, file cabinets, software you will use to keep track of your business investments, and a ton of other things. 

The tenant might honestly feel that you put shoddy/cheap/dangerous equipment into your rental.

But I would think tools purchased to work on your rental property would qualify as business equipment and qualify for section 179 deduction. 

This means not affording health insurance and another 3 years of stress until my equipment is paid off.

The equipment within may be able to be accelerated depending on other factors.  

If you are intimidated by threats you need to rethink whether you are equipped to be in this business.