1. I regret to say you cannot buy or sell something you don't own. Until such times as your mother dies and you children come to own the house, you don't own anything. A will is not valid and operative until a person dies. So, the will is not effective until death to transfer the house to the children. The death of your mother must come before the will is operative. Until then it is your mother who owns the house and it would only be her who can sell it. As she has dementia, she doesn't have legal capacity to sell it. You would have to get a Deputy appointed to handle her affairs in order to sell it for her. So, any talk about buying or selling the house is premature.
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