Proofreader for regular document checking

I run a design studio and often have to send pitch decks, presentation documents, even emails to my clients, and I would like to find a trusted contractor who I can regularly send documents to and that can send them back to me really fast (less than 24 hour turn around would be ideal). These documents aren't always text heavy, but I need someone who can spot a misalignement, or a design element that might be misplaced...
I am looking for efficiency, english language expertise, fast turn around, and most importantly, attention to detail.