user13433: I want use Bitcoin to make a purchase from a private seller in another country. The good which I want to purchase is priced in Euros, so I need a Bitcoin/Euro conversion rate which both of us must accept for the moment when the Bitcoin is transferred. 

user19097: Bitstamp is reputable and generally accepted in the context you've mentioned.

13433: <p>I want use Bitcoin to make a purchase from a private seller in another country. The good which I want to purchase is priced in Euros, so I need a Bitcoin/Euro conversion rate which both of us must accept for the moment when the Bitcoin is transferred. </p>
 19097: <p><a href="https://bitstamp.net/" rel="nofollow">Bitstamp</a> is reputable and generally accepted in the context you've mentioned.</p>
