Article writting for websites

Need an expert article writer. Need 50 articles to be written every month. The articles must have the following "terms": -100% uniqe -pass copyscape -no grammar errors -keywords are given,wich you'll have to use to write these articles -each article must have 500 word -keyword density 2%-3% Willing to pay $2 per article. Please bid for writing 50 articles. We want someone whom we can work on long term basis. Atleast 5 months or more.