Is it permissible to sell and divide a building owned by an elderly, sick man who has lost his mind, and what is the ruling on the divided money if the children and wife insist on selling despite it not being permissible?

It is not permissible to sell the building as long as the man is alive and has not been interdicted by the Sharia judge. If he is interdicted, the guardian will manage his assets in a way that serves his best interest. It is not permissible for the children or the wife to divide the price of the building or anything else as long as the man is alive. Anyone who does so is considered an usurper, and whoever takes a span of land unjustly will have it tied around his neck from seven earths. Their matter must be referred to someone who can prevent them, because aiding the oppressor is by restraining him.