How the scam works:
A couple of "plumbers" show up at your hotel door dressed accordingly, carrying a bunch of tools. It could also be a couple of "employees" saying they are checking the towels/minibar. The plumbing scam is more prevalent though.
They inform you the hotel has sent them to fix a plumbing issue and push forward with questions.
What will happen is one will keep you distracted in the bathroom with questions about the sink, shower, toilet, etc. for less than a minute, while his accomplice quickly robs your room. He only needs a few seconds to grab your camera, cell phone, and watch, and stick them in his coveralls.
How To Avoid:
Don't leave them out of sight at any time. Ensure they are both in the bathroom or same room at all times. Also, as a rule of thumb, any time you travel don't keep your valuables laying around, even in your room. Tuck cameras and other valuable equipment under some clothes in a drawer. Make sure valuable jewelry is also hidden. Use a money belt so you can keep your passport and credit cards close to you. Keep a wallet in an inside pocket and not easily visible. Know the area you are traveling and be aware.
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