Is the financial return generated from investing Waqf lands disbursed solely for Waqf buildings, or for the eight categories of those eligible for Zakat? And is it permissible to allocate a portion of this return to disburse as salaries for employees or as a financial return for the administrative building itself?

It is permissible to pay the salaries of employees in endowment departments from endowment funds, because the well-being of the endowment cannot be achieved without them. Sheikh al-Islam Ibn Taymiyyah clarified that the zakat (definition) collector, the endowment supervisor, the guardian, and others who act on behalf of others, are allowed to take a share from the expenses incurred by the money. In fact, he considered it obligatory to preserve the money.

As for the surplus endowment money beyond the needs of the designated beneficiary, it should be spent on others. If there is no condition stipulated by the endower, it should be spent on the deserving, regardless of their category. Ibn Qudamah stated in "Al-Mughni" that if there is a surplus from a mosque's mats, oil, or demolition materials, and it is not needed, it is permissible to spend it on another mosque or to give it as charity to the poor. He cited a hadith (definition) from Aisha (may Allah be pleased with her) regarding the old clothes of the Kaaba, where she ordered them to be sold and their price to be spent in the way of Allah and on the needy, explaining that it is the money of Allah Almighty and no longer has a specific use.