Im an agent, and out fees are clear and transparent
With BA we can void the ticket FOC the same day (until 2359) the day the ticket was issued
After which we get charged the Airline cancellation fee plus our admin fee which is £20 per ticket.
We have special corporate fares with many airlines that allow FOC refund or changes
Some airlines allow us the 24 hour rule, but this then becomes a manual process
Hope this helps