So you're saying that if I sneek into an abandoned building and live there, then the owner finds out, I actually have certains rights to stay there?

Is that an appropriate method to use to find the owner of an abandoned house?

Your tenants that have not paid you are either testing your ability as a landlord, were late payers with the former owner, or are saving up to move and abandon the premises.

When we first started Spartan, we dabbled in C props and Section 8 and abandoned them in favor of solid B/B+ properties because the expenses and headaches was just not worth it.

Once informed, I think most tenants would abandon the effort due to chasing and meeting the requirements.To show some 'humanity' on the issue, I would also make it clear the "sitting for the grandchild" certainly is not a problem.

I have an interesting situation that I'm not 100% sure how to handle. An 87 yo woman left her house and moved to another town. The house is not in a trust and the family is not interested to put the house on a trust. ...

Most of the houses I'm interested in are multi families or abandoned houses.

It is a great little house that looks abandoned.  

The agency identified on the notice investigated and found that the property appears to have been abandoned / left vacant.You can expect a Notice of Default or Lis Pendens (depending on your state) to be recorded against the property as soon as the lender gets around to it. 

You need an agent who will find properties, prepare comps, show disgusting, abandoned properties in sweltering heat (which I've done for the last two days in almost 100 degree heat) and submit lowball offers.Many agents won't.