The trouble for getting the documents, emails or anything you've written proofread is the worst, as you have already worked very hard in getting the inspiration, then writing it but then editing and proof reading is just as important as the other jobs you do to make it look good. And not being able to do so will keep you always unsure of your content's credibility. It always stays in the mind whether what you have posted or are going to post is correct. If it has incorrect words it can deeply harm your image as a writer.
I found this thing called GRAMMARLY very useful. It is great to subscibe if you write a lot and want to get it checked before submitting or publishing.