You are not giving the complete story. It is very difficult to help you thus. You are saying that the previous owner purchased from the builder. How can he purchase the Flat from a builder without paying stamp duty and registration. Amnesty scheme was for those who owned flats in open plot type societies. In the open plot type societies there would be no builder. A group of people come together, form a co-operative society, purchase land build a building and allot flats to the individual members. The ground will be in the name of the Society. Soceity would have paid stamp duty for the purchase of the ground. When the flats are alloted to members there will be no stamp duty as it is a consumer society. Until 1980 or thereabout co-operative societies were outside the Bombay Stamp Act and hence there was no stamp duty. Also co-operative societies were outside Registration Act, 1908. Hence registration of transfer of flats was not compulsory. Even after co-operative societies came under Bombay Stamp Act, many transfers were going on without payment of stamp duty. As the Government found it difficult to catch defaulters, they declared amnesty schemes from to time which was availed by some of the defaulters. Amnesty scheme is relevant only when a member sells flat to an outsider and not when a builder sells to a purchaser. If your seller had purchased from the builder there was no question of amnesty scheme for him. I suspect that he had told you a blatant lie. He may have connived with the builder to escape adequate stamp duty. When there is an amnesty scheme there must be a designated authority to give amnesty. Who was that authority? The document should bear the stamp of that authority. It is not possible to solve your problem through piece meal information. You give the complete history with dates from the date the land was purchased and the building was constructed. There will be no documents on stamp paper for flats in open plot type societies purchased before 1980 or thereabout. For instance I do not have a stamped document for my flat. I have only share certificate and allotment letter from the Society.
What is the collector stamp duty? And what is that amnesty scheme for collector stamp duty? The previous owner purchased from the builder. When the bulder sells the flat to a purchaser there will be conveyance deed for the sale of the flat. The buyer would have had to pay the full stamp duty and also register the document. There is no question of amnesty in that. The previuos owner had done somrthing fishy and lied to you. There would be other members in your building who would have purchased from the same builder. Please request any of them to show the documents which they have. Also ask them whether they have share certificate. The Society cannot be functioning if none of them had registered documents and none of them had share certificate.You talk to the Secretary in a friendly manner and ascertain from him how others had registered documents and also were issued share certificates. There must be a history with regard to your flat only, which you do not know. Investigate and find out that history and come here if your problem is not still solved.