have someone edit my book

I have written a non-fiction book of under 50,000 words and I need a skilled professional to provide both proofreading and substantive editing. Here's what I need:

- Proofreading: Ensure there are no spelling, grammar or punctuation mistakes.
- Substantive Editing: I need a critical review of the content. Help me improve the flow and structure of the content.

Ideal Skills:
- Proven track record in proofreading and editing non-fiction books.
- Excellent command of English, with an expertise in grammar and punctuation.
- Strong communication skills to provide clear, concise feedback and suggestions.
- Detail-oriented with an ability to spot minor errors and inconsistencies.
- Experience in substantive editing, with an ability to provide constructive feedback on book content.

Please provide examples of previous work when bidding.