If someone doesn't pay, add the person to your blocked bidders list then file an unpaid item dispute against the 4 days after end of the auction. Four days after that, close the dispute. The non payer gets an unpaid item strike and you get your final value fee credit. Additionally, non payers cannot leave feedback.
I do not know if it available in India but if you can, send items using some sort of recordable delivery method. Something that shows up online as being delivered to the recipient. This will help you win item not received disputes.