No buyer can resist a domain that is pulling in whopping sales and has a brand name seared into the minds of a profitable target audience. Generally a domain is worth the amount of sales it creates in a year. Boost sales by offering low-cost products that can be mass produced. If hot demand can be created, you can sell thousands in no time. You can also rack up big annual sales by offering a pricey service that appeals to a lot of people in a specific industry.
Higher prices are almost always the quickest way to double, triple, and quadruple sales.
Finally, work to establish your domain as a well-known brand name. You can pull off brand name awareness at a smaller level by keeping your ads consistently in important places, putting your name on key websites, writing articles that make you look like an expert, and participating in your industry's major Internet discussion groups.