Dear Baskaran,
You should speak to the local authorities for getting the exact bye-laws for construction on the land that you plan to build. Depending upon the locality the bye-laws differ greatly. The process usually works as below.
1) You check with the Town-Country planning office, or Urban estate development office to understand whether a marriage hall can be constructed on that piece of land. The property dealer who is acting as a middle man for the purchase should let you know the office that you need to visit.
2) Once you know the authority name, you can visit the office and check with them whether you can use the land for a particular use. Each land is marked for a seperate type of usage. For example, a residential land may not have shops, offices or other commercial establishments.
3) The department would also tell you the paper work they need for approvals.
4) NEws paper advertisement or approval from Neighbourhood RWAs would not help you if the govt does not allow a particular type of building on that land.
5) Once you are sure that you can construct the marriage hall building there you can engage an architect to plan the building. Some architects would also help you get liason with the local authorities for approval.
6) The cost calculation and other things come after the plan is appproved.
Let us know if you have more questions.