One of the most important ways to sustain profits in your niche-related business is to create new products and service that your targeted audience will be eager to buy. You can accomplish this in a number of ways.
The most obvious is the new product launch. If you know your niche well, chances are you should have a pretty good idea of what they really need and how much they are willing to pay for it. In other words, you will only create products that you are certain will sell.