Buyer not paying for the goods I sold him
I am writing on behalf of my cousin who is a small business man from Ahmedabad, I kind of hawker supplying pan-masala, bidi-cigarate to pan shops. He buys the material from whole-sellers and go round the city on scooter supplying to the pan shops. His monthly turn-over is around Rs. 1.5 lacs. The payment condition is that previous amount has to be paid by the buyers to buy new stock. There are some 4-5 such pan shop owners who are not paying him since 3-9 months. They have not only stopped buying materials from him and started buying from other sources, but refusing to pay the outstanding. Each time they promise him to pay in next round, but they never pay. Upon him becoming aggressive, one said "Do whatever you want, I will pay you when I wish to pay. Do not come to me asking for money". The other said "If you want money, talk in low voice. Do not raise your voice, else you won't be paid a single penny" One said "If you force me to pay you, I shall call the police and get you arrested". The other one said "I can pay you Rs. 10 daily. If you want then come from tomorrow". (the amount this person owes him is Rs. 7500 and is 8 Km far from his house). One person even threatened to beat him if he goes to him asking for his due. I adviced him to go to police and file complaint against him for thretening, but he said he cannot go to police because there is no invoicing system in his business. The whole-sellers do no give bill to them, nor do the pan-shop owners ask for bill, hence he shall have no proof of that particular person having bought materials from him and of owing money to him for the same. Someone advised him to give-up and forget the money else that person shall file a case of extortion against him, hence afraid, my cousin has stopped going to him. The total amount all these people owe is around Rs. 25000 which is his profit of more than 2 months sale.
Please advise what should he do to recover money from his debtors.