IF the family wanted to do it, the kids were involved, and everyone understood exactly what was happening, its not a bad idea.
If you were going to do this, you'd want the heirs involved and signed off on it under separate documentation and to fully disclose exactly what was happening. This WILL complicate the sale, but it is really the only ethical way to do it.
It isn't a bad concept, you can get above market for the house, fully funded life insurance that pays out on death of the principal, and both the residents do not have to move out of the home.
Sorry, but I disagree. Don't forget...they just lost liquidity. What if they needed the cash? Do you think the agent would loan them cash from the commission he received?