Hi
Since the seller(Directors and Sale Head) have committed to you in writing(by email) that they will refund the money in the event of cancellation before 20 December 2017, the Seller has to repay all of your monies to you without any deduction whatsoever.
a) As an NRI, you should send them by email (to their corporate mail ID) the Notice of cancellation.
b) In the same notice you should also ask for them to refund the money.
c) Actually if you had entered in to an agreement, probably the money paid by you would have been treated as advance payments and the sellers would have been at liberty to deduct a percentage of money(as costs) and refund you the balance
d) In absence of agreement, your money is a booking amount and as per law all booking amounts needs to be refunded without any deduction.
e) Please keep all your communications in writing by email.
f) If they have confirmed to you orally that they will inform you in writing on the date of repayment, you should put it down in writing by email.
g) There can be a delay in refunding your money. But delay cannot exceed 90 days. For delays in excess of 90 days, the seller needs to pay you bank interest rates as cost.
h) You need to ensure to keep in touch with the seller through mail.
i) Given that we have Real Estate Regulation Act, Consumer forum etc which are very strict with real estate guys, the builder might delay the refund for a short duration of time. But beyond a certain period of time (say 4 months from the date of payment), he cannot avoid the refund as law will catch up with him.
j) Even if you are based abroad, your lawyer can conduct the proceedings under RERA /Consumer forum. Your presence is not required for filing the case
Hope this information is useful.