Probably the easiest and most accurate way to find the "real" owner of the property.

That's simply called speculation (also known as gambling)!

The quickest way to get what you want is to ASK for it.Your target market seems accurate, but I suspect that very few brokers will help you find these deals.

I've been using Sperlings (www.bestplaces.net), but sometimes I wonder how accurate and up to date their data is.

How accurate can that be?

I sent several people to investigate and no one could accurately find the source so I informed them they need to let me know right away next time it leaks and take pics or videos.

Do you find those type of statements to be accurate or do they often entail more work than is actually needed?

I have some general numbers but would appreciate some more accurate info to start running the numbers. 

May not be accurate. 

Of course, there are other numbers to take into account if you want to get more precise, like appreciation/depreciation, plus the opportunity cost of the dead equity....but to say owning a house is purely a liability isn't totally accurate.