If your company is growing beyond its own marketing capabilities, hiring a marketing agency might be a smart move. Here’s what to look for. Q:We’d like to get started with a marketing and PR firm. What suggestions do you have for hiring the right fit? —Robb McKerrow, vice president of store and brand development for five-unit, Atlanta-based Chepe’s Mexican Grill A: How exciting, Robb! Your company’s decision to engage outside marketing resources indicates it’s ready to make a significant investment in the future. To pick the right marketing agency, there are a few things you should consider. Set...