And someone DID answer your question. Just in another post

Quote Originally Posted by Taeth
I think out of the amateurs only the decent looking fighters or better make 5000+ in their fight, but the pay raise for the best is very steep, and if they fall its a long way down, but an average fighter I would be suprised if they made more than 60,000$ a year... and thats a pretty good average fighter at that... I know Corley was made like 125000 against Mayweather, and he was a world champion who gave Judah a tought fight already.