Cover Illustrations

My eldest son said I could pay him whatever I wanted for the covers to the Shatterworld Trilogy he is working on. He did not think it fair to charge by the hour as I said I would because he is learning a new program and using the illustrations as the practice piece. So let's see, the first time Shatterworld alone was published I think the illustrator was paid $400 by the publisher. So three times 400 times the inflation from fifteen years ago is....something to contemplate. I hope my son takes payments.