I have been doing proofreading for over a year now. I go through each and every word to check for any spelling or grammatical error. I also edit the articles or blogs, if required and give valuable input wherever required. I can work on a short notice as well. On an average, I charge $10 for 500 words. Rates may be slightly higher, if I have to work on a really short notice, but I can assure you that the work would be done with 100% perfection.