I suspect this is a case of £5 for the final icon, £580 for the other 10 comps and three rounds of meetings you had to go through to decide on the inverted vers

I suspect this is a case of £5 for the final icon, £580 for the other 10 comps and three rounds of meetings you had to go through to decide on the inverted version in the first place. It's trivial to recreate the end result, but you can't ignore that the end result wasn't a foregone conclusion; ideas had to be floated and presented and agreed upon, etc. Especially with high-politic clients, getting consensus on even a small thing can take a lot of time.