My brother @kingcent, while I appreciate the fact that your idea will save cost but I think even if your father duplex or mansion it's better to live a distance away from your parents and care for your own family, if your father have another house that is not the exact house that he lives in you can move in to the apartment, if there are 10 marriages that the couples live together with there parents 9 among them are affected negatively is just a tree to maintain that initial peace with it wife and mother, in-law since most mother-inlaws expect perfection from there daughter in law and when there expectations are not met with they get irritated and that often give rise to problems at home.