Hi there MeMe1960,
The Bahamas sound like a great trip! Managing and restricting usage is definitely beneficial, to help avoid any roaming charges. On your iPhone, if you go into settings> Cellular> and turn off Roaming, your device will not work for calls, texts, or data, outside of the country. But if you are connected to Wifi you will still be able to send iMessages and use features such as Facetime, without a worry.
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