1) Cops may try to stir up trouble when none exists so it's important to know that one has to stay calm. Shouting or trying to disagree with them doesn't help. reason it out. also if one is being Fined for something make sure the receipt is for the amount you paid and nothing less.
2) Beggars and roadside vendors may try to fleece you of money by making up sob stories. it's they're job. try not being too soft hearted or you may end up spending more on them than on yourself.