Selling a grant before taking possession of it
Question

                Is it permissible to sell the number of a land grant given by the state? Please note that the land has not been handed over yet, and the person does not know when the handover will be completed; he has only been given a number by the municipality in which it gives the date of application and the number of the application or the grant. He has sold this number to another person and has taken the money on the basis that on the appointed date for the handover he will go back to the municipality and complete the handover procedure, or he will give the buyer authority (power of attorney) to complete the procedures and transfer the land to his name after that.
Praise be to Allah.This 
    transaction is not permissible, because this comes under the heading of 
    gharar (ambiguity, uncertainty), and selling that which one does not have. 
    The Prophet  (peace and blessings of Allaah be upon him) said: “Do not 
    sell that which you do not have.” Narrated by al-Tirmidhi, 1322; classed as 
    saheeh by al-Albaani in Irwa’ al-Ghaleel, 1292. 
Moreover the value of 
    this land may fluctuate with time, so this transaction involves ambiguity 
    and uncertainty. 
And this 
    number is simply a promise which has not yet become the possession of the 
    one who has the paper or number, so how can it be permissible for him to 
    sell it? The Prophet  (peace and blessings of Allaah be upon him) 
    forbade selling that which a person does not possess. Moreover, he does not 
    know where the land is located. It may be in an area where the price of land 
    is high, or it may be on the edge of town, or outside the town in an 
    undesirable location. And he does not know whether it is in the middle of a 
    residential area or on the edge; on a main street or a back street; whether 
    there is one street, or two or three? All of these factors will affect the 
    value of the land and people’s interest in it. 
Based on 
    this, it is not permissible to sell the paper with the number on it, the 
    details of which he knows nothing about. Rather the owner of the document 
    should wait until he gets the land and the grant is executed in reality, and 
    he gets the deed to the land which proves that he owns it and defines its 
    location and size. Then after that he can sell it if he wants to. 
And Allaah 
    is the Source of strength.