What is the ruling on exercising ijtihad in distributing Zakat al-Fitr to the poor based on an estimation of monthly income and family needs, and is it obligatory to inquire about whether they have received Zakat from others, and what is the maximum amount that can be given of food or money to the entitled recipient, and does the recipient's acquisition of Zakat al-Mal affect their eligibility for Zakat al-Ta'am (food)?

Zakat al-Fitr is specifically for the poor and the needy, and a strong presumption that a person is deserving of it is sufficient. It is permissible to give one poor person the Zakat of several individuals, and there is no need to ask the poor person if they have received Zakat from others. If it becomes apparent that the person who received the Zakat is wealthy, it is still considered valid. Scholars differ on the amount that should be given to the poor. Some say it is sufficient for a year, while others say it is sufficient for a lifetime, such as the Shafi'i school of thought, and this is supported by the hadith of Qabisa ibn Al-Makhariq. If the poor person is given what suffices them for a year, then the Zakat payer has done well.