Is it just and equitable that I am only entitled to the rent of the lower-valued apartment (350 pounds) instead of the original rent of my apartment (600 pounds) after it was changed, especially since my father and siblings knew about and agreed to the change and that the difference in rent would be mine, but then they recanted?

The questioner is advised to come to an understanding with his family. He is not obligated to obey his parents in divorcing his wife. Indeed, divorcing her is not an act of filial piety towards his mother. Therefore, he should convince his parents of his decision. It is not permissible for a father to differentiate between his children in giving gifts, because that engenders enmity, hatred, and severance of kinship ties among them, unless there is a legitimate reason. Accordingly, he does not have the right to benefit from the excess rent of the apartment without his siblings, unless the apartments are owned by those to whom they were given and the siblings agree to that, or there was a legitimate reason for the preference.