Probably, this woman is trying to scam you, but even if she's not, YOU SHOULD STILL START AN EVICTION.

I was contacted yesterday by a woman looking to sell her house.

The property is owned by an elderly woman who was recently widowed.

The elderly woman is now in assisted living, so two properties are involved.

I'm not sure which podcast you're referring to but I know one from a few months back had a woman that was sub-leasing without the owner's permission.

They see a 40-year-old woman driving a Lexus and wearing nice clothes and assume she must be rich.

An older woman just moved in a SFH and complains of being constantly cold. 

The brother in jail is still in touch with the woman and won't the sign the property over if it means his ex is kicked out.

In this instance this woman has been a homeowner (and previously living in a new house) so there are two strikes against her liking being a renter and living in an older place.I do like the suggestion that, if she continues to be a royal pain in a low spot you either consider offering to let her buy your house (if you are interested in selling it) or offering her the "Happy Clause"; however, in doing the latter you'd have to return any unused rent.  

I had a woman almost get ripped off on one of my properties with the copied rental advertisement scam, fortunately, I happened to be there working on some things when I noticed her in the backyard.