If I was a mistborn I would be a jack-of-all-trades mercenary/hitman. You would send me the fee of acceptance (money just to look at the job), a picture of a person, and a metal to represent what you want to have happened to that person. Steel means assassination, iron means protection, copper means I need to hide them and bronze means I need to find them. Zinc means to publicly shame them, brass means to blackmail them. Tin means to observe them, pewter means give them a beating. (All of this is in jest considering my personality would hinder me in so many ways)