This is a great idea for a niche portal. If you are interested in starting an online directory that consists of easy-to-make mini-sites for businesses that cater to seniors, for example, then check out my signature below
Such a site can also show coupons, but within the more comprehensive information given in each business mini-site. This means more value to the business owner who signs up and pays you every month than simply listing coupons.
I can show you exactly how to set up your portal, get businesses to sign up and then get your message out to the seniors in your community or district. And it is all really cheap to set up, and can make good money. You can run it yourself or hire someone to help you.
If you have any questions, please contact me (email is on the page in my sig). Best of luck with your venture, whether you take me up on the offer or not!