It's easy to shoot holes in a budget plan that is without a plan. Come to board meetings with graphics that illustrate the alignment among professional development/curriculum work expenditures, district initiatives, and the means by which you will hold everyone accountable (including yourself).
It helps to develop a three-year plan that shows expenditures being applied to the attainment of meaningful goals (this is where the initiatives come in). The community will be comforted knowing your plan is part of a far-reaching vision that will project costs without surprises.
I've also had success providing my Board of Education with expenditure projections for major purchases such as textbook adoptions and instructional technology equipment. The plan also frames my budget for the next several years and makes the process that much easier when it comes time to plan for the next fiscal year.
All of these documents should be made public; transparency is key. Make sure everyone knows these are "living" materials that can be altered for very valid reasons.