Value of Land

Which land value to consider? This question may seem to be illogical as in most cases the value of land to be subtracted from the cost of the flat is nothing but the sale consideration as mentioned in the sale deed registered for the sale of UDS portion of the land which is also its market value / guideline value fixed by the Government on which stamp duty is paid. In certain cases the sale consideration mentioned in the sale deed and the market value of the UDS portion of the land (based on which stamp duty is paid) are different from each other. The market value of the UDS portion of the land gets mentioned in one of the schedules contained in the sale deed and stamp duty/registration charges are paid based on the market value of the land mentioned in the sale deed, then the dilemma arises as to which value of land to be subtracted from the cost of the flat for arriving at the taxable portion or construction cost of the flat for levying service tax. I kindly request you to clarify which value is to be considered as the value of the land for subtracting it from the cost of the flat for computing service tax? Thanks & rgards, SIVARAJA