Nice! I don’t understand about the art though- could you explain a little more?
Artists who do commissions usually charge depending on how much they have to draw. For example, a full body would cost like $10 or something, while drawing waist-up would maybe cost $5 (sorry if this is a super bad example, it just popped into my head.)
You would also need to attach some sort of form here so people know what to fill out. Like this:
-Form for art commissions-
Character details-
How many characters-
Pose and reference-
Payment method-
Just something like that, to give you an example.