Article for Health website

I need the first of several articles written about colon cleansing and very closely related topics. Once project won by service provider, I will provide a keyword list to be used as the theme of the article. The article needs to be between 500-700 words long using those keywords, and should be completed within 3 days of acceptance of project. I would like to see samples of recent work done, and confirmation that the copyright will be my own once finished. The cost needs to be around $20 per article, and I'd like to see an outline (headers) that we agree on before the article is written, based on the keywords provided as well as my ideas for it.