The cost of land (NIS/sq.meter) can vary by 200x or 300x depending on where you are located. A dunam of land in downtown Tel Aviv, 110 meters of sea-front property or a prime residential block in Yerushalayim will obviously cost a multiple of several hundred dunams in the middle of the Negev. Perhaps you could clarify what type of land you are considering purchasing, for what purpose and the general location.