shankar (self) 23 June 2012
K.K.Ganguly (Advocate) 25 June 2012
Proper advice can not be given before seeing the Agreement for Sales. I do not find any material reason for him to ask for such a letter from you. If you write such letter you will admit your not abiding the payment clause which may empower him to cancel the agreement, if such clause is there in the Agreement.
Try to avoid giving such letter.