Dude .... khata is the actual legal document which gives u owenership of the flat..... it is like dakhil kariz in north india. ... Stay away from Alpine Eco... the ownership of land itself is in question.. It was a land of some reddy brothers inherited from forefathers. .. but the inheritance itself has a legal issues now as their are more parties showing up ownership. The builder had just done agreement with the land owners to build apartment on partnership basis ...... contact some property agents in that area every one will tell you the story...