There is a tool used against artists. Some people think that it is a substitute for money. The claim is that it will gain the artist a lot of business, and therefore the artist should reduce their fee. However, artists tend to forget that the job they do will earn them this anyway, regardless of whether they were paid or not. The device they use against artists is called exposure.
We've all heard it before. "Let me have your art for a cheap price, and I'll get you tons of exposure." Yes, exposure is a value, but it won't pay the bills. It is only speculation for future business. Future business that may or may not happen. Take the money instead.
As an illustrator, I painted Star Trek novel covers for a number of years. They sold millions of copies, but I never received a single commission from those covers despite the exposure. Don't count on exposure.
The other tactic is to offer the artist a lower price with the promise of more business later. Don't fall for this one either. Get paid what you are worth for the job you do. If you aren't sure what to charge, try this: figure out how much you want to make per hour, estimate how long it will take you, multiply the two numbers......Then double it. Simple.
The next time a client offers exposure of future business in lieu of money tell them "no thanks."