Want to buy resale flat in Pune want to know the legal status of land

Hi, I am planning to buy resale flat in Pune wakad. This flat is 5 years old and owner of this flat is landowner who has given his land to developer and Developer has built Co-Operative society on it. I have got following documents from Landowner: 1) Development Agreement 2) Deed of Declaration 3) Completion certificate 4) Sanction Plan 5) Property Tax bill 6) Light Bill Owner of the flat is saying he has not got any allotment letter or Possession letter from builder and details of flat is mentioned in Deed of Declaration. I am confused now if this property is legally clear or not? Do i need to take separate search Report? As i am taking loan from bank