Sales transactions amount show procedure

How the payment of Rs 20 lacs made at the time of purchase of land?

Payment through on online mode wife bank account rs:20 lacs

Property is in who's name??

Property name for husband and payment through on wife bank account and purchase value not show in books and it returns.

The purchase can be recorded in books by showing that you received gift from your wife and property is purchased from that money, and purchase of property is nowhere shown in IT returns, only sale is shown.
Now, since you have recorded the purchase value of property then you can easily pass the sale entries and calculate the capital gains.

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