I was chatting with an investor from Tenessee. He used to invest in tax sales/auctions but now he finds abandoned homes with defaulted tax-bills:

Pays the bill
Occupies the abandoned property
Files a lien against the property for the amount of the bill


Is this plausible? Purportedly he's been doing this in several midwestern states. I want to know how this would be done. I wonder on what basis it would work in California.