How To Write A Business Proposal To Sell A Company . Scroll down to read the first part of this sample. Introduce your company to your buyer. The outstanding 035 Sample Business Proposal Templateoc How Write from www.pinterest.com Include a cover page, contents page, executive summary, business description, financial data, list of assets, list of liabilities, future business projections, sale offer and an appendix. This free business sales proposal letter is designed to help salespeople write a great letter that helps them pitch for new clients. Now it’s time to present the cost for your product or services.