Article rewrites required

I require articles which vary in length, 400-550 words, to be rewritten. The articles are in many different subject areas. I've listed my requirements below. I want the rewritten articles to have/be: 50% different from the originals keyword density between no higher than 5%. new titles and subheads grammatically correct. about the same length as the originals I will pay up to $2.50 per 400-500 word article. Please let me know how many articles you can manage each day. I will want articles rewritten Monday to Friday every week if the successful bidder produces good work. I want each day's articles emailed when they're finished, every day. On this project I will pay by Paypal as the work is finished and done according to specification. The articles will be used for website content and I require native English speakers. I'm looking to develop a longer-term relationship with high quality content providers. Anyone who places a bid will need to provide me with a sample of their writing style. If you pm me I will pm you a small sample of an article to rewrite for me. Any questions, please ask. Copyright in the rewritten work will pass to me with payment.