Sales Channels are created at the Institution level.
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Require confirmation email: If checked, a customer using a guest login (if it is activated) will need to provide two times his email address (to avoid errors in typing).
Maximum Payment : leave empty if you don't want to set a maximum amount of online purchase. If you set a cap, the customer will not be able to buy online beyond that limit. On the other hand, his order will be kept as a reservation for which you can take payment at the counter (for example) with another payment method.
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