In this article, we discuss how to write a business proposal letter and we offer sample letters and templates you can use as a guide. Detail how vendors should format and submit their proposals, including submission deadlines, contact information, and any required documentation.Instantly draft and send a business proposal template to establish the terms and conditions between your business and clients. The time and date of submission will be marked on each proposal when received in the State of North Carolina Integrated Purchasing System (IPS). Vendors shall populate all attachments of this RFP that require the Vendor to provide information and include an authorized signature where requested.