On our most recent visit we just signed up online for Verizon's $10-per-day plan which bills you only when you actually use your phone. Maybe AT & T has something similar. Verizon's weekly plan was something like $70, and we don't use the phone that much when on vacation. In fact, we actually called and texted the states on just one day (mother-in-law, sons, etc.) to see how things were going, so our bill should increase by just that $10 amount and nothing additional. Maybe that's an option for you.
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