Julia Rowling its SOP  (standard operating procedures) to not put any appliance's in these homes until the tenant moves in.. same with HVAC some times  condenser unit water heater etc etc.If you install them new and leave them for any length of time they will get stolen nearly 100% of the  time... this is why I have said many times that these types of investments just are not appropriate for anyone who does not do this for a living...

Even though she technically breached the lease, you probably still have to follow certain procedures.

we had a guy abandon a small barn we rented.We followed legal procedure & eventually everything was sold off.

Not a factor.Keep in mind the paperwork and procedure requirements of Section 8. 

Does anyone have a Standard Operating Procedure they use when one of your rental units goes vacant?

The more I document what I am doing, and the procedures that we are following, then I will be able to delegate those tasks to a VA and we can focus on more income-generating tasks. 

Other than taking their word for it, is it standard operating procedure for contractors to carry proof of insurance with them so I can see it when I ask them about it?

Let her know that as a matter of procedure, you'll be posting a Pay or Quit on the 3rd day (or whatever is legal in CA), but you're willing to work with her to avoid eviction.

Make sure to check with your States statutes to make sure you are ok with this procedure, every state is different 

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