I never allow my customers to trust me with what they want. I either bring a few magazines and let them decide the pattern or go all the way to the fabric store with them and ask them to select the colors and maybe even buy her own fabrics. It seems a lot cheaper to them because I only charge for the labor, thread and batting.
I make mainly wallhangings and when someone mentions they like something I have made I show what I have already and they either buy right there, or ask for one in particular on different colors or different size.
Is better to be open from to the start to prevent dissapointment.