Grab our best tips, methods, templates, and samples for writing emails to submit your proposals. Want to learn how to write proposal emails?Complete a buyer's persona. Acquiring the products and services you need to complete your projects starts with your RFP email to vendors. Greet your customer in a friendly manner and demonstrate how the value you provide matches their requirements. 1. Start with a warm greeting. We have reviewed ten of the best proposal templates we could find online across various industries. These proposals showcase multiple proposal formats. Professional services proposals define the scope and timeline of a project. Get it right and it helps you win more clients.