Please place your bid for rewriting 6,000 words. I assume it would be $32 with the rate you gave me for rewriting 1,500 words previously.
I would clarify that the 6,000 words means the words that would be counted AFTER you have rewritten. I mean if I give you 1,500 words to rewrite, and after you rewrite them, they become 1,400 or 1,600 words, then I will count those 1,400 or 1,600 words that YOU have written.
Most importantly, there won't be any plagiarism. I check all the works through plagiarism-detection scanners.