Now that your book is nearly ready for printing, why not make it the best it can be with a professional proofread? 
Even some books printed at some of the best publishing houses, still have grammatical and spelling errors, or even missing words.  When you're working so closely with your story, it's impossible to see all the pesky errors that slip through.  With a professional proofread you can rest-assured you will have the best grammatical version of your work.
 
This is charged out at $25 per 1000 words - a deposit is taken here and an invoice for the balance will be issued prior to completion of proofread (minimum charge 4000 words)