What is the ruling on an incompetent person (safeeh) making an endowment (waqf) for himself?

The prodigal (safih) is one who does not manage wealth well. Such a person is interdicted and prohibited from disposing of their own funds. A guardian is appointed to manage and grow their wealth, from which expenses are paid in a reasonable manner and zakat is rendered. The prodigal is prohibited from making donations, such as an endowment (waqf). Scholars differ regarding the ruling on a prodigal establishing an endowment for themselves. The majority of jurists prohibit self-endowments. Others permit them, holding that the property does not leave their ownership. If a ruler decrees the validity of a self-endowment, then it is enforced. An exception to the prodigal’s prohibition from donating is when they establish an endowment for themselves and then for a charitable cause after their lifetime. A will (wasiyya) and تدبير (tadbeer - a form of manumission tied to the owner's death) are valid from a prodigal purely for the sake of benefit.