How is the inheritance to be divided among the children (two males and one female) after the death of the father who built part of the property, and one of the sons completed the construction of the remaining part with his own money, and are the construction costs for this son to be calculated at today's price or at the price at the time of construction?

What the deceased leaves for their heirs is to be divided among them according to the prescribed Islamic distribution, which dictates that the male receives the share of two females. This is based on the Almighty's saying: "Allah instructs you concerning your children: for the male, what is equal to the share of two females" (An-Nisa:11). So, if he leaves behind two sons and one daughter, the inheritance is divided into five shares: two shares for each son and one share for the daughter. As for what one of the sons built with his own money, its ruling depends on the details of the father's or heirs' permission. Previous fatwas on this matter can be consulted.