Grab our best tips, methods, templates, and samples for writing emails to submit your proposals. Want to learn how to write proposal emails?Professional services proposals define the scope and timeline of a project. Get it right and it helps you win more clients. Learn how to craft an effective business proposal email with our comprehensive guide. Instantly draft and send a business proposal template to establish the terms and conditions between your business and clients. I am writing this letter to commit the support of XYZ Systems to the Mechatronics Engineering. This proposal email template is designed for impressing clients with your achievements, social proof, or positive testimonials. This is a onetime opportunity that we would hate for you to miss out on. What is the average size (employee workforce) of your customers?