Exchange Property

Hi. I And My brother live in a single 2000sq.ft bunglow.. My brother lives on ground floor which is registered on his name. And i live on first floor registered on My name. Terrace And parking are also diveded 50_50 Now we want To exchange it. I want To tak half of his ground floor in exchange of half of My first floor.. So that each will get 1000 sq. Ft plots.. What should be its stamp duty And how it will be calculated. Pls any one help me. Regards Manish batra