Do it for free
One of the most annoying techniques people use to get lower prices when buying online is to claim that they found someone else who’s willing to do the same work for a lower rate. Oftentimes sellers see right through this, because logically if you had someone else offering you such a low rate you would just use their services.
This was a pretty low-quality attempt at getting the artist to produce a free banner. We’ll give a couple points for the semi-polite “plz,” but still, this is just ridiculous. Why don’t people understand that goods and services are actually worth money? The world as we know it literally would not function if everything was free.