Please . If they are going to ask for a Commission. Please "have the money at hand".

It has already happened to me with several people that I make a "Sketch" of what they want and then I send them the Invoice, And they disappear without having paid me...

It's not fun to waste time on something they ask and from there they never get paid. u_u

Please if you are really interested, ask for Commissions and pay for them. Sometimes I'm disappointed by some users... T_T