A budget needs a revision historyConcept A: Provisional inputs; Budget v1: Scope + exclusions; Design change: Describe the difference; Budget v2: Keep old baseline. Re-price assumptions instead of silently reusing rates.A budget needs a revision history01Concept AProvisional inputs02Budget v1Scope + exclusions03Design changeDescribe the difference04Budget v2Keep old baselineRe-price assumptions instead of silently reusing rates.³Ô¹Ïtv • explanatory diagram, not a production or inspection record