A wise man once said, "Often the best solution to a management problem is the right person." Choosing an English editor has never been easy. However, there are a few factors that can make one proofreader better than the other. I'm willing to prove to you how good I am when it comes to editing and proofreading. I am an American native English speaker, but currently, I am living in Egypt due to some family issues. I have mastered the SAT, which is a national exam that assesses how good a student is when it comes to certain skills. The SAT has an editing section and an essay writing section, and I have mastered all of them, scoring 800/800 on my English section. Further, I got 4/5 on my AP English test.
I guess if I were you, I would have known who to hire right away.
Good Luck, sir!