You can generally trust Jamaican people just like any people,
but if you are staying in a resort city, like Montego Bay or Negril,
the bottomfeeders and parasite people come out of the woodwork. They will
wait for you just outside of your hotel, or on the beach, as "ripping
you off" is their profession.
Some call them Rastabums. Picture giant mosquitos, buzzing in your ear, following you, trying to get their blood-suckers in you. While you are trying to walk down the beach, you will notice in the distance, rastabums positioning themselves to get right up in your business. "HEY MON!" right in your ear, over and over, until you don't even want to ever come back. As you walk down the beach, they will call at you from their beachhuts. "No cost to look", they will yell at you, and try every trick imaginable including intimidation and even threats. -- It's that bad.
As you walk down the beach, you will also notice a few poor lost souls (Tourists who haven't learned the ropes) sitting with them, trying to think of an exit strategy.
While you sleep, you will still be hearing "YAH MON!" echoing in your head from the incessant badgering. Then you will spend the rest of your vacation in your hotel. -- OR, you can adapt your behavior.
The worst thing you can do is look like the smiley faced American or European. This is almost an insult to them to see you. They have a severe jealousy and even hatred for the rich sheltered foreigner. The first thing I learned, was to walk around with a dead serious look on your face, almost like your suffering, like either your mom died, or you have a bleeding ulcer. There are many white Jamaicans that live without any problems from the locals.
To them, it's funny and cool to mess with the foreigners, to rob them of everything, to trick you into giving them any money at all. If they give you anything, they will expect money.
Some of these con-men even want money for talking to them, even though you did everything to avoid talking to them in the first place.
Never make eye contact unless you have to, keep your eyes on the road and your destination.
If you are with a friend, and someone starts yelling at you, immediately turn to your friend and act like you are trying to make an important point, even making hand gestures. And just act like you don't understand them, and can't even hear them.
If you are with a local, they will almost always leave you alone.
When they yell at you, don't even look at them, if they come up on you, keep walking. Try everything you can to not say a word to them. Don't look angry, look serious, and keep moving. Like your mom needs your help, and nothing in the world is going to stop you.
I would suggest meeting people that work at your resort, and asking them to take you to see "Real Jamaica" because if you just stay on the beach and around your resort, you will miss the real culture of the country. You will also think that Jamaicans are all Rastabums, and this is not the case.
I would say only about 1% of Jamaica's are tourist predators. I met many more real Jamaicans than the pressure salesman scoundrels.
It's hard to imagine how many tourists have been so turned of by the hustlers that they decided to never return to Jamaica because of them. Imagine the other effects as well, like permanent prejudice of Jamaicans (These conmen are mostly who the tourists meet, so they think most Jamaicans are this way), and the economical side effects, millions of dollars lost to legitimate business, and tourism decline.
Put up signs on the beach or in the resorts telling tourists to avoid the rastabum. Make it illegal to try to sell something to someone after they say "No" one time. Tell people to report anyone to the police that continues to hound tourists.
Round up the worst of the huslters one at a time, then put them on work duty in the middle of Jamaica, or put them on a special expedition to the Antarctic, just kidding.
Jamaica is a beautiful place, once you get away from the rastabum areas. Make Jamaica a more beautiful place, Get rid of the con men, and boost the world's opinion of Jamaica, while helping the economy of Jamaica.
Make it illegal to follow or continue talking to a tourist after they say a key phrase like; "No thank you, I'd like to continue on my own now".
Make it illegal to try to continue to try to sell a specific product or anything after someone says "No", "No thanks", or even waves their hand or shakes their head in a gesture of "No". It's just impolite the way they don't take no for an answer, even reverting to intimidation.