Are the children from the first wife entitled to their own accommodation, similar to their siblings from the second wife, and is the father's expenditure on his divorced wife and children in his home considered a favor from him or a duty upon him?

A father is obligated to provide housing for his children, as this is part of their maintenance. If he allocates apartments for them to live in, he has fulfilled his obligation. As for his divorced wife, her maintenance is not obligatory after the 'iddah (waiting period) expires. Scholars have differed regarding the obligation of housing for the custodian and the payment for custody.