Need expert native writer for search engine optimization and marketing topics

Need well-researched and informative articles written with an interesting pitch. Topics will seo related like why manual directory submissions are required for better SERPs, how press release can help you get high traffic.. I need only expert writers who have good knowledge of seo and marketing niche. No re-writing stuff will be accepted. I'd request all sources at the end of each article. Price - $3.5 per article (450 - 500 words) Writer or team must be able to do minimum 4-5 articles everyday (5 days a week). Each article will have 3 variations of titles. These article will keyword targeted but we don't want any keyword stuffing. The keyword should be highlighted only once in the article or you can use it naturally wherever it comes. Each article should have 2-3 different keywords appearing once. Payment will be made on complete of each set of 20 articles. Escrow will be used for people with nice feedback. For new providers, I'd like to go for payment after every single article. Attach your sample in PM .. NO Bid will be entertained without sample on related topics. Articles should be error free and written in excellent english. Immediate start would be appreciated. You must be able to meet the deadline and provide error free articles with good grammatical and sentence construction things. If not, we reserve the right to cancel the project without any payment. Plz bid for 13 articles. (don't bid if you don't accept the rates) Right candidate will have good flow of work from 15-30 articles everyday (for teams)