There are VoIP adapters which are able to connect POTS instruments to a VoIP access. They're almost certain to cost less than a cellular adapter.
Of course, I'm asuming that you have Internet service and would keep it no matter what the cost of each option.
Bill
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No broadband there. Hence the cellular request.
Every time I read about cellular devices repacing copper pairs, I remember the job my brother had in South America: he was building solar-powered cell sites for a subsidiary of GE.
He told me that every site was located on a mountaintop, accessible only by helicopter.
Bill
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