Property is on my name but have no documents
My father has total 27 acres (7 acquired from ancestral property and bought 20 acres while in service ) on his name . Recently(in 2013) due to some conflict on my fathers side , he immediately transferred 5 acres each(which included ancestral property of 7 acres) to me and my sister (once and for all) . I have done 2 years job in infosys , I tried going to US but dropped due to financial constrains . Wrote some competitive exams but in vain . decided to start a business by selling part of my land since No bank will accept it as collateral as its govt rate is somewhere around 80 thousand but its market price is somewhere between 7-8 lacks (per acre) . But unfortunately I dont have documents .
My parents legally divorced in 2005 and then my father married again in 2007 . probably remaining 17 acres land may be on my step mothers name in which I have least interest. Also we have a independent house valued 1 crore in Hyderabad which is also I am least interested . He is emotionally blackmailing to marry some girl on my step mothers side in which also am least interested but hes saying he might transfer everything on my step mothers name if I disobey him.
All I want is to secure the land which is on our name(me and my sister) . But we dont have documents . In gram panchayat and district tahasildhar office , it was registered on our name officially . But documents are missing . i would like to know is there any remedy legally regarding.