Hello :o)
I am an American Native, and as you can see by my test scores, I am proficient in American English.
I have recently completed proofreading and editing a three book series, and the author was very happy with my work. I also proofread a screenplay just a couple of weeks ago, and it went very well, the writer was extremely happy with my suggestions and feedback. I have a lot of experience proofreading and I'm sure you will be happy with my work.
When I was in college, the English department hired me to be a tutor, and I quickly became the "go-to gal for students that wanted A's on their work.
I believe that communication is very important in a job like this, and that it can make your work shine as you want it to.
I look forward to working with you! I'm sure you will be happy with the finished product.
Best Regards,
Gaylene