Return Of Token Amount Against Buying Commercial Office Space

Dear Sir / Madam , We wished to sell our office space in mumbai and found a buyer . After negotiation we concluded on a price and he gave us a cheque of 50,000/- as token money . Balance he said would be paid at registration after 15 days . We only signed a receiving on a A4 Paper saying we have received 50,000/- against the said premises and balance would be paid at registration. We did not sign any sort of contract or agreement . However a month passed by and we did not hear from the buyer or from the broker so we ( Seller) decided not to sell the property due to personal reasons . Now when we are returning his cheque of 50,000/- he is claiming more expenses of additional 25,000/- as lawyer fees to draft the agreement and newspaper add of 10,000/- . He sent a letter by registered post seeking these expenses also as reimbursement . We did not tell him to hire such an expensive firm for drafting the agreement or publishing the advertisement . Buyer did it at his disposal and wish to satisfy himself !! Please tell me what shall I do in this case. I just want to refund his 50,000/- and close this chapter .