REGISTRATION COST AND STAMP DUTY

I am going to purchase a 2nd hand flat in Kolkata. WB govt. side market value is showing Rs. 32Lacs but sale consideration value is Rs. 40 lacs. 1.how much amount I have to pay for registration cost and stamp duty charges(it will on market value or sale consideration value)? 2.Can I make the "e payment" for registration cost and stamp duty via 2 bank accounts or I have to pay via single bank ac? KINDLY ADVISE ME IN THIS REGARDS.