A Proposal Form must be completed prior to the submission of a grant or contract proposal to an external funding agency. 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.Please refer to RFP Proposal Instructions for guidance in completing this proposal. The City of Sacramento is seeking proposals for vending products and services from vending machine operators. The Letter shall state the complete name, or business name, of the Proposer making the Proposal. Letter of support must be from an entity with recognized expertise in the area identified in the proposal. The letters should address (1) familiarity with the. All items should be addressed. All items should be addressed. Indicate contact person(s) for the firm.