Superior serialized information products are an excellent source of revenue because they can be released in installments, which generate interest in your membership site and products over an extended period of time. (It also gives you multiple opportunities to contact the media and send announcements to your list). Possibly even better is the fact that serialized products sell for more money. Courses, tutorials, and even books work wonderfully as serial products. Audio interviews and training videos work well too. If you already offer information products on your site, consider breaking one of them into several small parts and selling them as reports. This gives members the option to purchase just one report at a time or they may be enticed into buying the whole package, and if a member chooses to buy just one report and is happy with it, there is a good chance they will buy several more, making you a reasonable amount of income.
Your most profitable market will always be customers who have already bought from you. So make your product sales skyrocket. This means it will be easier to concentrate on making money from back-end sales rather than trying to get new customers. The principle of back-end sales is that when a member buys one product from you, you tailor your marketing specifically for them to encourage them to buy something else, usually of higher value. Besides that, you also can focus on upselling. Upselling is a straightforward concept. Use it to increase the revenue you produce from individual product sales on your membership site. When a member buys one product, you simply offer them additional products to complement it, possibly at a reduced cost.