It can be quite small. He knew what trade magazines his customers read. These writers get paid if they sell stories to the magazines. So he put together some interesting story ideas that were convincing enough for a freelance writer to put together a sellable story. Some time in researching and a few phone calls.
Telephone calls from all over the country and tens of thousands of dollars of sales.
Plus he got reprints of the articles and used them in his promotional materials for use with customers and to sell future stories. If this sort of creativity is not one of your core competencies then you should consider retaining a professional PR firm. Companies hire PR firms to make good things happen for them as cost-effectively as possible. Positive, extensive and regular media coverage is almost never an accident for publicly traded companies and never-ever is an accident for privately held companies. The problem is that effective public relations is a process that evolves over time .