Here in Australia I just recently read a story about paid off house identity theft type fraud. The person impersonated the overseas owner and sold their house because it was easy to obtain a copy of the title on a fully paid off home.
Now there's no recourse for the owner as the person who bought it was unaware and it's just a mess.
If the owner left it mortgaged , but fully offset, it would never had happened, because banks require all sorts of IDs and docs.