All of which we self manage from all over the country.

I believe we have a strong case if we go to court but already spent around 8K on lawyer fees.

If rent is still not received in my office on or before the 11th, then on the 12th day I can file that Notice to Quit in a court of law, and it is at that time that the courts will setup a court date for us (usually within 10 days, making it around the 22nd of the month). 

I live in NE TN where real estate prices are some of the lowest in the country.

Yes the 4 children who want to sell can.In Oklahoma any of the owners may file a Petition with the Court asking that the property be "Partitioned."

Tile is also more traditional in those parts of the country than wood. 

If a court of law didn't convict her, why would you hold it against her?

It takes about 5 minutes on the clerk of court's site.

It doesn't go on their record, you don't go to court, and it is just a NOTICE to them that their rent has not been received.But even though it is just a Notice, it is imperative you send it to the tenants the first day rent is late because you can't even begin the eviction process unless that Notice has been sent. 

This way, it is considered rent and can be part of a rent court issue rather than a more difficult/separate civil court issue.