I take a totally different approach if I am i the United States or Canada vs the Caribbean. Street wise security in the Caribbean is paramount. Caribbean cruisers are known for taking precautions that would seem excessive in North American. Most of my friends switch wedding rings when they fly down for the season so that a valuable ring is not shown, credit cards are never left out of one's sight at a restaurant, etc. We have all just learned that caution pays. A druggie who can make $10-$15 per day working sees someone with $75 in cash is tempted, knowing also that the likelihood of criminal penalty is low.
When you start assuming which places are safe and which are not, you put yourself at risk. Don't assume that any place is safe. Not your gas pump, not the pharmacy, not the grocery, not the restaurant, not the marina. I'd never carry enough cash that I wouldn't be fine just handing it over and writing it off as gone. I've never been mugged but know people mugged or who have had their purse or wallet taken in places you'd never suspect.
As to cards, I know it's at risk every time I carry it, every time I use it, and even when I don't use it. Most of the time when we hear about theft of information it's well after it happened. When we get compromised in other ways it's generally sooner but often some delay. The credit card processors get compromised. Every store is at risk. Ultimately, it will happen. The main thing we can do is be quick to discover and remedy. I had an $82 charge on one card in a place I haven't been, from a business I'd never deal with and at a time, I had not used it anywhere I would have thought of as risky. No idea what happened. Charge reversed, card canceled, new card the next morning. The bank doesn't know what happened and their fraud department will only know if there are multiple similar transactions that tie together. Then they'll look for something common to all cards.
As to jewelry, I don't really know the answer. I do know what I don't think it is. I've seen people get copies made of their jewelry but not real stones. However, look real until you get very close. I don't see that lessens the potential of attack at all, just the value taken, and it's the attack I fear most. We're careful about where we go. We go much of the time in groups, but never just one of us. We keep on the lookout. We know it can happen one day and we'll be 100% cooperative before we'll put ourselves at risk. My wife does not wear her wedding ring or other flashy jewelry when we're out sightseeing. We try not to look like good targets. It's like when I traveled to various cities and countries on business, I tried to never look like a businessman. No briefcase and definitely no computer case. No suit. No coat and tie. I'd at most carry some sort of cheap, small duffel bag.
My wife will wear her ring and jewelry and designer dress when we have a dress up night and go to a fancy restaurant or a musical or symphony or something. However, then, we'll drive or take taxi or uber or limosine and not wonder away from our targeted destination.
One other thing. Often thieves work in packs, not singularly. Sometimes one even serves as a distraction. Someone comes up and tries to start some conversation that makes no sense, don't get sucked in. Guy walking alone and some hot, scantily clad girl walks up to him and tries to engage him, nothing good is likely to come of that. We see it in retail where one will try to engage and distract the clerk.
Ultimately theft of cash or hacking of credit card information is likely to happen to you. Just avoid injury and risk of life.
As to the boat we have good security systems.
I will add one comment on locations to what Pelican said. Wherever you are away from home remember you're the outsider. If you get into some dispute or brawl outside your home area, you will very likely have many witnesses against you and for the other guy. We use to tell employees who would visit El Paso, not to under any conditions take a car to Juarez, only taxi, and if you did sometime take a car and have a wreck, leave the car immediately and get back across the border. Once had a NY employee who decided to go to a bar and then hit on a girl there in the Delta of Mississippi. He took her back to his motel room. Later, and the facts are unclear on exactly what happened as his story was definitely a lie, a guy showed up and beat him badly, the guy and girl disappearing quickly. Another employee was called a few hours later to pick him up at the hospital. As the police didn't believe his story, they made no real effort to catch those who did it. I honestly think they felt he deserved it.
For you single men, if it seems too good to be true, it probably is. I was once getting on an elevator in Dallas and this gorgeous, scantily clad young girl got on at the last second. She struck up a conversation immediately asking if I was visiting, alone, getting close, playing with her hair and pressing no button on the elevator saying she'd just get off with me. Now, I wanted to think it was my good looks and incredible charm, but as I'd used no charm, I knew it clearly wasn't and she was danger. I didn't let her follow me into my room and wasn't even happy that she saw what room I was in. She knocked at the door and I didn't answer. I called the front desk. They said they'd send security to check the hallway and seemed surprised. The following morning I saw three policemen in the lobby and spoke to them. They'd had a businessman rolled in his room overnight, the third one in the last week. His money, jewelry, ATM card, and credit cards gone and him left handcuffed to the bed. He didn't seem to want the case pursued though. They surmised he probably didn't want his wife to know.
