If your people are selling to senior executives (which they should be in this economy), the answer is the shorter the better. I've done million dollar deals on the strength of a two page proposal. My proposals are typically five to ten pages. When I see proposals that are 30 and 40 pages long, I cringe. No senior executive is going to read such lengthy documents. In the case where you must include detailed technical specifications in a proposal, put these in an appendix. Keep the actual proposal as brief as possible.
Remember, the purpose of a proposal is not to educate. The purpose of a proposal is to request a specific course of action. It should be brief, clear and motivational. Follow these steps to make your proposals clearer:
1. Start with your understanding of their requirements. Never begin your proposal talking about yourself. Demonstrate how well you listened by succinctly summarizing their needs. This builds trust and confidence.
2. State your proposed course of action. Be brief and be clear.
3. State your methodology. How will you help them achieve their goals? Include pricing and timing. Put technical and marketing details in an appendix.
4. State what they will get as a result of implementing your offer. Make sure it's what they are looking for.
5. Be clear on what they must do next. This is your actual request. Executives love when people are brief in giving context, prepared to give more detail when asked, and clear about what they want the executive to do.
The power of this approach lies in how the human mind works. This approach satisfies the cortex, limbic and reptillian parts of the mind. Try it and see how much more quickly your proposals get acted on.