Work backwards from revenue targets
Start with the revenue goal, apply average order value and close rates, and calculate the leads required. That figure, multiplied by expected cost per lead, is your budget floor.
Separate testing from proven spend
Ring-fence a portion of budget for experimentation. Without it, an account slowly stagnates around whatever worked eighteen months ago.
Review quarterly, not annually
Channel efficiency shifts throughout the year. Quarterly reallocation keeps budget aligned with where returns are strongest.