Share certificate is gud but do these things: 1. Check with the Govt records office as to who has the title to the property in question. 2. When u are willing to buy this flat, give an advertisement in a national daily stating the same and state whosoever has objections may prove their title. 3. Very important, get a lawyer..u dno’t wana screw up the whole transaction and an expensive transaction considering u r buying a home in mumbai, just beacause of a bit of lawyer fee..ryt?