Buy supplies like Zippers in bulk… good idea? Sewing Machines Parts and Sales in Los Angeles

I know it would make sense financially to buy zippers in bulk among other supplies… but I don’t necessarily know what colors I might need down the road for projects since that would depend on the project.

Do you buy zippers or other supplies in bulk? If so, where? and how do you deal with not knowing what fabric you are working with in order to choose the colors?