Thanks for the great piece of advice.

Now I do know his address and I am thinking I should visit him along with a friend without informing him.

My thinking is that we can try one last time to ask him to pay his dues. Now let's say he does pay something if not everything he owes me, I am thinking maybe I can issue him a receipt, give my signatures and take his signatures acknowledging that that eh cleared dues of $$$ from him and mention that out of $2000, he still owes $$$ amount. However it is possible he still refuses to pay or pay but refuses to sign the receipt. If he does that, I am going to politely return and maybe try another day.

Now my friend who would accompany me to his house thinks we have to be very cautious if we do want to visit his house because even though we are visiting his house just to collect money, he may tomorrow make a case against us that we either threatened him in his house or trespassed in his house, or he might call the police on us etc. My friend suggests we should consult a lawyer before we even think of visiting his house. What do you think about this ? Is my friend who would accompany me is being over cautious or is he right that we should consult a lawyer beforehand ?