Freelance article writing on Marketing, Media, News, etc

Looking for freelance article writers WITH EXCELLENT ENGLISH ACADEMIC SKILLS to develop unique content and summaries on marketing, social media, brand strategies of popular companies, etc. 50 articles at 400-500 words each for $50 and future commissioning of work if happy. I will provide topics I want covered for some of the 50 and you can come up with some and ask me before writing them. Each ad will need to be accompanied by a relevant (high res preferred) picture. I WILL CHECK for plagiarism through various programs. If found you will not be paid. Please provide portfolio and sample work you have recently done. Time is 30 days, would like 25 articles done by 15th day and if satisfied will release half payment. On 30th day will get the other 15 and release the second half of payment if satisfied. dont bid over $50