Mark Harris wrote:
"The basic proofreading needs to check the grammar/spelling/referencing system/vocabulary using/sentence structures(if necessary). Based on the basic proofreading, copy-editing(deep proofreading) requires rewriting or additional editing to make the language to be more academic and "sounds native". Paraphrasing is to rewrite every sentence to avoid plagiarism/reduce similarity rate."
The first is a common job for papers at postgrad levels. The second is really not advisable for anyone not involved in the project/programme, and certainly shouldn't be done by anyone who doesn't have deep knowledge of the subject area. How can a proofreader retained for their skills as a native speaker (not as a fellow academic) start rewriting some academic paper? The third is probably illegal and certain to be unethical. There's a Turkish agency that specialises in just that. I encouraged ProZ.com to ban them but they wouldn't.
"I pay £5 per 1000 words for basic proofreading, £8 per 1000 words for deep proofreading and £15 per 1000 words for paraphrasing."
Wow! I've done quite a bit of the first type of job this month. I submitted my invoice yesterday for €30 per 1,000 words. And I believe that's quite a low quote.
"Payment will be made within 24 hours once we received the completed work."
Ah, the sweetener. They think every freelance supplier is so desperate for money that they'll do this job today, get paid tomorrow, and be grateful for the pocket money .