My client had purchased one flat from one well known builder, while purchasing the flat the builder assured my client that he will give my client a balcony/terrace attached with the flat. Accordingly he registered the agreement to sale stating the area of terrace in the document. Now he is refusing to give the same, as he has already consumed the F.S.I. and further he revised the building plan and put the terrace on 4th floor. Now I want to know how to proceed against the builder. I have much less knowledge about these type of litigation. Kindly help me.