You don’t bolt a community on to your business. You integrate the community into your business. This means changes. You need to change your company, your products, your promotion, your pricing and perhaps even your distribution. Jerome McCarthy would be thrilled.
You company has to change. You're building a community with your members, not for them. This means collaboration. It means your employees working with the people you want to reach. You need staff willing to interact with members of the community, respond to questions, discuss ideas, befriend members etc. You need to be able to react to what the community says within the organization. They should feel like they’re on your team.
Your product or service will need to change too. Feedback from the community should be intregrated into what you sell. You might include a free invite to the community in the packaging of the product. You might make a souvenir version just for community members. You might give community members a discount.
Or better, automate it. When members purchase the product or use the service they instantly have a community member's account.
A community should be integrated in your promotion too. Give members exclusive information first. Ask members for their idea to help market the products. Try using your advertising and marketing resources to promote the community for a change.
Change the website too. Make the community elements of the website the central elements. People will visit your website more frequently. Ensure activity from the community is in a prime location on your site. Put the static information to the background, bring the community to the foreground. This is a place where members can chat about the products, as well as buy.
You should consider charging a premium for members that want to join the community too, or offering discounts to community members. Give bonuses or free products to members that are the best community members. Consider offering a premium option that includes community membership and entrance to relevant events.
There are many, many, ways to integrate a community into your business. You should consider all of them. The better integrated your community is within everything you do, the more successful it will be.
If you’re not prepared for integrate your community into the very core of your business, then why are you bothering to create one? Better, why would your member bother participating in a community which isn't integrated?