We went to a bank for an education loan for my son to study abroad showing our flat as collateral which is registered in 2006.we have original sale deed ,and EC of motherdeed from 1990(16 years) onwards we have given the EC.They are asking for 1987-1989 EC.That time the plot was registered in Chennai.Chennai people are asking a memo from Jayanager office. Jayanager people asking us to pay the difference in registration amount.for the plot(3000 sq foot) on which 8 flats(one is ours) are constructed. Our builder is not willing to pay the amount.Now the bank is telling to pledge our fixed deposit of 16 lakhs. we need to pay an upfront interest 13.5% for the loan amount of 17 lakhs which comes around 5lakhs and 80,000. Since we both are not working we have to pay this interest now itself. And since the EC is not available(1987) they are advising us to go for registered mortgage . For that again we have to pay some amount. Please advise.