Nixon - I live in your community and have plenty of real experience (successes and failures) with adverse possession deals. That is probably what the squatter is attempting to do.

I've actually tracked deals in Chino Hills, which not common, however vacant abandoned properties occur everywhere; even in upscale canyon area where I live. Even beach cities and Beverly Hills!

Since I've been involved in literally thousands of probate (and pre-probate) deals over the years, no one dies without heirs. Hard to believe, but it's true. I'm involved in two related estates now (as admin of both) whereby mother and daughter died without close relatives. They did leave some distant "shirt-tail" cousins, whom I found and signed up.

Hence, I've got a deal and superior standing to the squatter that thought he was so smart. Sold that property and now dealing with next estate (plus many others).

The only ones I haven't figured out how to research are FBI informants who have undergone identity changes. But I haven't given up, either.