Is it permissible for the wife to demand full ownership of the property and pay the difference, or is it only permissible for her to hold the husband accountable for the money he received while he remains a partner with her in the property?

If a husband and wife agree to co-finance the building of a house without specifying percentages, then the participation is to be equally split. If it becomes clear that the husband did not contribute financially, but only used the wife's money, then he owes her half the cost of the construction. The wife has the right to demand half of the construction cost and whatever was taken from her money for purposes other than the house, unless she donated it. They may agree that the wife will own the other half of the house in lieu of her money. Each of them should know that taking the other's money is not permissible unless it is with good will, and that every body nourished by unlawful gain is most deserving of the Fire.