I'm trying to come up with a system for determining the level of expert craftsmen within a city, (weaponsmiths, for example) and I was hoping someone might know of some general guidelines for this or even a random generator. I would assume that the larger the city the more likely the odds of higher level experts, and the higher level the expert the rarer they are. And I have some ideas on the average levels of expert craftsmen as well as a method for randomly determining their levels. But I wanted to see what others may have to say on this.