Buying a house in Mortaged layout

Dear Sir, I came to know of a property for sale, in a layout where my brother owns a Villa, Builder ran into problems and stopped construction, the owner of the villa has now put the semi finished villa on sale, we have calculated only the land value and offered to buy the semi finished villa, at 71 Lakhs, I have paid 21 Lakhs in advance, and wanted to go for home loan for the remaining, while arranging the documents for the home loan, I came to know that this villa and another 40 villas in the layout of 9000 villas are mortgaged and the amount due to the bank is 2 crore, and value of each villa is 1 crore. if the total amount is divided among the 40 villas, each need to pay 5 Lakhs to the bank. so it will cost me 71+5 L (76 Lakhs), if i take only the land value of this property is currently valued at 90 Lakhs. Please advice, if i can buy this property by paying the remaining and register on my name, and later when it is decided by the bank and 40 villa owners to repay collective, i will pay to the bank. is there any risk in this deal. i don't want to loose this villa unless the risk is too much. Please advice