I agree with @iala4 that important sections to include are 1. Background 2. Objective 3. Scope 4. Time frame 5. Project budget 6.Key stakeholder. I also agree with @f-dot that a realistic budget and timeline are key. With the projects that I deal with if we contract out the development we look for the company to provide an extensive timeline with a gnat chart and to summarize the major milestones/deliverables and a budget that is broken down into different phases. So Phase O is the planning phase where the detailed gnatt chart and plan are organized, and budget for Phase 1a/Phase IIb are established. Overall, I think there are different titles/sections that can be included in a Project Proposal, but to get buy-in from key stakeholders its important to have a clear/realistic timeline and budget.