Be aware that any listing will be in one and only one currency, based on which eBay site it was set up on. You are required to pay the seller in the currency of the listing, and any "approximate" conversion that eBay displays is ALWAYS too low (based on "mid-market rate" quotes rather than the retail "buy rate" you will need to pay someone).
In eBay Checkout you have the option to have eBay bill your payment source in the currency of the listing (for expensive items it is well worth your time to compare your payment sources to see which has the lowest buy rates and compare it to the quote you get from eBay's payment processor) or have eBay's payment processor do the conversion at its buy rate (which is about 4% more than the "approximate" conversion shown on the selling pages--I have no idea why eBay doesn't use those rates instead of the "mid-market rate" to calculate the displays). If you choose to let eBay's payment processor do the conversion (which I'm pretty sure is the default) you will be shown the total you will be paying in USD before you commit to it.
