Lease of flat

Dear sir, the matter is explained below: 1)Steel Authority Of India Ltd. in its troubled days during the period of 1999-2001 sold its company quarters to its employees on 99 years lease which were renewable every 33 years at no cost. 2) several employees bought the quarters on lease. 3)The main conditions was that beside there use if the employees decide to dispose the quarter in the lease duration then they can do this only to a SAIL Employee . 4) also any existing employee who purchases the quarter will have to surrender any quarter alloted to him by the company . 5) now i am a SAIL employee and i have 12 years of srvice left . i am due to retire in 2027. 6) i wish to buy one quarter leased to a SAIL Employee . 7) i do not want to vacate my present quarter allotted to me by the company. 8) i want the lease deed to be executed in 2027. 9)how can i do so and get the possession of the quarter i need to purchase . 10) is there any type of option contract can be made so that the quarter is given in the name of my wife or me on rent till the period of my retirement and then i get the lease deed executed. 11) how can an agreement be drafted so that i get the possession of the quarter from today and get the final lease deed executed in 2027. 12) i have to pay the entire purchase amount at present. 13) if the seller dies in the mean time then how can i be protected. thanks