Big house built on revenue site (green belt) but got e-khata (a)

Have you seen the A khata physically and whether you verified it's genuineness through the BBMP website?

If not please ascertain the facts first instead of listening to false information.

All E-khatas are not A khata.

Without construction plan approval the owner would not be able to obtain A khata, hence you obtain a second opinion from a different advocate before venturing into the proposed purchase.

Yes, I have also downloaded the Khata online, just to be sure. It's an A Khata and genuine one. It also has photo of the house that is built by the owner.

Since it is a revenue site, according to the Karnataka act "The farm building or farm house so erected shall not be more then 10% of landholding". In this case, the owner has built a 2500 sq feet house in 4000 sq feet of agricultural land, which is a clear violation. Along with that, the layout is also not converted, and it is an agricultural one. The seller owns one of the plots in that agricultural layout.

Even after this violation, somehow, the seller managed to get A Khata with a house photo in it. I wonder how it can be? Is it risky to trust A khata nowadays?

I believe this will cause issues for future buyers.

I managed to get it checked with 2 advocate, both told "Go Ahead", one advocate told that Akrama/Sakrama will be applicable and second told everything is fine. But my research suggests otherwise and I feel it is very risky.

Karnataka has a functioning Lok Ayukta. The issue could be taken up with them.