Q: What is Online Marketing? Online Marketing including search engine optimization (SEO) costs an additional $0 to $1000+ per site plus monthly fees. Costs depend on how competitive your market is, how large your website is, and how much exposure you're looking for. If your business is local and you live in a small town, website marketing costs may be as low as $100 or less. If your business is local and you live in a large city, $100 to $500 dollars. If your business is national or international, prices will vary depending on the nature of your business.