Hi, I have a question about airfare reimbursement. I am organizing a conference. One of the invited scholar wants to fly a business class. He knows that we can only reimburse him the amount of economy fare, and is fine with that.

I guess my question is... how can he get an official document which states the amount of economy fare? There are so many different rates even for a economy class of a same flight. Would the screen capture of the economy fare on the airline website be enough? I know I should consult with the organization we got the fund from. But is there a standard procedure for this sort of situation? Does anyone with a degree in Event Management know the answer?