As people are carrying cash less and less, these SumUp wireless credit card readers look like they may be a good idea for orienteering events. The website says no monthly charge and a reasonable commission. The models in the links below don't need to be paired with a phone so it should be possible just to pass the units from one organiser to the next, along with the SI gear.
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Has anyone any experience of them?
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https://www.sumup.com/en-ie/solo-card-reader/
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https://www.sumup.com/en-ie/3g-credit-card-machine/
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