Is it permissible to purchase free bank cards for a price higher than their nominal value ($10 for $10.15), and sell them for a higher price ($10.50), while setting a fixed selling price regardless of the exchange rate, and how are these cards delivered to points of sale and payment received hand-to-hand?

It is not permissible to work with usurious banks, even if the work is in an area outside of usury, due to the prohibition of cooperation in sin and aggression.

As for Islamic banks, it is permissible to deal with them. Selling pre-paid cards for a value greater than their balance is permissible if the currencies differ, provided there is equivalence and immediate exchange when the currency is the same. Handing over the pre-paid card is considered an immediate exchange ( قبضًا ), as is paying its price via bank transfer or certified check.