She doesn't like living next to a vacant house, AND the guy was arrested on some serious drug charges.

We think she may have started drinking again (she has had problems in the past and just learned of several current warrants out for her arrest related to multiple DUIs, one of which resulted in bodily injury of the people in the other vehicles ) It sounds like the consensus is to just sell the property to one of the cash offers that I've received recently and let them deal with the foreclosure process if that's what it takes, that must be the move. 

They already have assigned someone to head the arrest and trial against him.

Can he be removed by the authorities...well now you're getting into protective orders and arrest, trespass etc.

If the day after you open a HELOC on your primary, there's a shiny black Porsche in your driveway, is your bank patrol going to knock on your door and say, "Excuse me, sir...you're under arrest and we're confiscating your home"?

No pot farms, nope they can have as many plants as they want and cannot be evicted (but may be able to be arrested for breaking the law).  

I simply haven't been hearing the druggies talk about meth at all; I haven't heard of any apartments being used to cook meth; and I haven't been reading about any meth arrests.

Have you ever been arrested or charged with a crime other than a traffic violation?

I have googled his name, and (2) minor arrests show up for driving on a suspended license.Any advice??

As mentioned several times a local attorney should be able to help you and it could quite possibly fit the criteria for criminal prosecution (arrest) for theft.