They claimed to be a "good friend" of the previous tenant.

There was another BP'er that claimed my comments were advising the OP illegally, which is not correct. 

The population is holding steady over the past 10 years - no growth but no contraction.Current landlord:-Bought the property for $40K in 2016 and it and others around it have significantly appreciated since-Claims he is selling because he is moving and getting older-Property is occupied on a month to month and he claims they would consider a long-term lease. 

Eventually I can get her new address and then sue her on small claims.

You'll be amazed how many people have claimed they will empty the rental only to discover they've taken a few items of value and then left you with everything else.If they haven't provided a point of contact, or if you want to confirm the point of contact, you can always visit them at the location where they are detained and ask them.

This bill is over a month late.Today they paid a some money and claimed it is for rent. 

Real estate brokerages in their training of agents claim this is the most effective lead generation although I think I have the odd demographics of people I know who aren't even in houses to begin with.3)  Get more lists for idea 1 by targeting houses in forbearance; divorces; and probate.  

I can't tell you how many times I've rented to someone that claimed they would be there forever, only to watch them leave before the first year is over.

Can he file a quit claim deed to add me to his title and then I apply for a HELOC on the PA property so we can make improvements and buy an investment property?

@Teri Feeney Styers I'm on call 12/7 (that's half of 24/7) at a medical clinic.