If you’ve built a resource guide that provides clear value to your users, you can certainly start thinking of ways to monetize it. One of the common ways of monetizing resource guides is providing the visitors with a free sample (e.g. a few items from each category) to get a taste of the product and charging for the full database. Other monetization options include ads, a subscription-based model (makes sense if the directory is frequently updated with new entries and/or there are additional services available for paid customers), partnership with featured companies to earn affiliate commissions, and so on.