I'm Ann, from the team here at Shopify :)
At this time, there wouldn't be a simple way to change your currency for one person in our POS system. You would essentially need to update your Shopify admin settings within your store, and then change them back in order to get this done, you can see the steps on how to do that here. However, even doing that might cause complications with your payment provider as they are usually set up to work with the currency your store is using at the time.
That said, I can see how more fluidity with currencies during the checkout process can be beneficial, so I will let my developers know about this feedback! Maybe we will see a feature like this in the future.
I hope this helps clear things up! If you have any more questions or concerns feel free to reach out to us here :)
Have a great one,
Thanks Ann, but it doesnt work, because, the amount of this invoice will be different, its like Potatoes an Tomatoes, compitly different.
We want to have the summary in one currency USD, but if one client want to pay in another currency we want to do the option.
The main problem, its that in Costa Rica, the country that I have the store, the currency exchange vary to much, and we need to sell in USD its a most, but the invoices need to be in CRC colones.
If we set the the store in CRC, we lose money because we bougth all the items in USD, and one day the exchange will be vary.
Example: the cost of my product its $1 and I sell for ($1.5usd, like ¢873 CRC) if tomorrow the exchange vary and i sell the item in Colones the same 873 colones its $1,45 we lose)