my friend got a plot from real estate promotors.they got Rs.3,50,000/-for the land of 3.5 cents. but it was regitered for the value of Rs.1,50,000/-..now document is in poseession of promotors. they are asking further 5 lakh( market value) from him to handover the document. he signed in deed at registered office,without reading the contents of the document. further he signed in another document that was also registered. .Has he give remaining amount. what will be the another document (is there any liability for my friend)
