Know-How Exchange : Other

As a general rule, you're better off paying them on a per-post basis for the content. Without knowing more about the target audience or the industry, that's what I would suggest. That also leaves you with greater leverage potential.

The main reasons an expert will contribute insight to your website are:
a) Increase their own name recognition among your audience;
b) Attract that audience to their website or company/product; and
c) Gain increasing authority.

Serve these interests by offering the contributors a picture, a short bio and a link to their site (or whatever they are interested in promoting, such as a new book or conference). Then, to signify that you want quality content, offer to pay a flat fee for the post, and specify the length range you want for that fee. This separates your site from those who want content for free, and thus get mediocre content -- the kind of mediocre content that Google is now trying to push to the margins.

This compensation should take place on a per-instance basis. To make the link portion of the compensation more valuable to your experts, take the time to install quality SEO on those article pages. Great search engine results help you, but they also make your site an attractive place for experts to place their posts.

As a business practice, it is prudent to severely restrict the number of people to whom you offer a percentage of your site's income -- for instance, your business partner or your financial backer might be the only people who qualify for this list. If you promise to share your revenue more widely, you're passing your income to people who will never care about your business as much as you do, and you're removing the funds you'll need to develop the site further and to acquire additional expert posts.

Bottom line, compensating on a per-instance basis allows your business to stay on budget while your site prospers. Best of luck to you.