How is the zakat calculated for an amount of 300,0 dinars invested in a real estate project, taking into account the rise in land prices, the sale of an apartment during construction, and various expenses, and is zakat calculated on profits immediately upon their realization or after the completion of a full year (hawl)?

There is no zakat on inherited land, even after it has been prepared for trade. Zakat becomes obligatory on its value after it is sold, provided that a full year (hawl) has passed over it and each heir's share reaches the nisab (minimum threshold). If trading begins, each partner pays zakat on their share if it reaches the nisab at the end of the hawl. The hawl is calculated from the time of possessing the money after the sale of the land. The value of the land and the building together is subject to zakat at the end of the hawl, and debts are deducted from the partner's share. Profits do not have a new hawl; rather, they follow the original capital in the hawl.