1. In normal scenario if the purchase value is less than the stamp duty value or circle rate and the difference is more than 5% one needs to pay tax on such difference amount u/s 56.
2. However if the property is received under a public auction by court then the value paid in such auction would be final value and no need to pay any additional tax.
Was the property auctioned by NBFC was through public auction by court or government authorities, If yes then you will get benefit of point no. 2 and that will be your cost of acquisition.
If no then you need to show difference amount as your income as mentioned in point 1 and then that increased amount would be your cost of acquisition.
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