Contract selling is selling your client on a three-to-five-year contract with the stability of price, quality, and delivery. Of course, there is much more to this agreement, but the basis is to avoid having to sell your clients each year. This allows you and your sales staff the time to expand your business in the area of sales without any additional salespeople.
This same principle can be applied to buying from our suppliers. I suggest going to your prime supplier; I qualify a prime supplier as one you buy the vast majority of your raw products from. This idea is not for every supplier you have, but those you do the most business with annually.