- Who is more entitled to obedience, the parents or the husband, in matters that do not involve disobedience to Allah? - Is a father sinful for buying a plot of land for his only son with the consent of the other heirs?

The rights of parents are great, as are the rights of a husband over his wife. A woman must balance between them and give each their due. In case of conflict, the husband's right takes precedence. As for your father buying land for his son, that falls under the category of favoring one child over another.