Dear Neha,
If he is a builder who is owning a land also, then he may opt for the abatement of 75% on the total value including the land value and would not be able to claim the cenvat on the input services. [Refer Notification No.26/2012-ST dated 20 June 2012]
If he is merely acting as a developer, then the service tax would be chargeable as per Rule 2A of the Service tax (Determination of Value) Rules, 2006, wherein you may opt for
1) an option for segregation of labour and meterial and thereby claim 100% cenvat; or
2) an option for charging 40% tax on the total contract value but you will not be able to claim any cenvat on the inputs.
I have referred for various provisions, that you may refer for better understanding.