One of the biggest wastes of money that companies (big and small) experience is designing a newspaper/magazine advertisement - only to run it one time. Please take our advice! If you're only planning on running a print ad once, don't run it at all. It takes an average of 3 times to get a prospect to realize you're there and in the market for them.
Design something great! Engage your customers! Then distribute it appropriately. Whether it means smartly placing your ad in a magazine with editorial that focuses on your firm's product/service, or placing a stack of brochures on the right countertop of the storefront next door.