Finance Analysis via Bottom-Up Estimation + Reconciliation
Pitch
Build a bottom-up financial model from tasks, resources, and unit economics, then reconcile it against top-down estimates to surface gaps and improve accuracy.
Why
Top-down estimates are fast but coarse. Bottom-up estimates are realistic but time-consuming. Combining both gives the speed of top-down with the credibility of bottom-up, while exposing unrealistic assumptions early.
Problem
- Plans often include partial or inconsistent financials.
- Bottom-up models are missing or unstructured.
- Divergence between top-down and bottom-up is not tracked.
Proposed Solution
Implement a bottom-up estimation module that:
- Extracts work packages, resources, and timelines.
- Builds cost and revenue from unit-level assumptions.
- Aggregates to totals and cash flow.
- Reconciles differences with top-down estimates.
Bottom-Up Estimation Framework
1) Work Package Extraction
Identify:
- Tasks and milestones
- Deliverables and work packages
- Staffing requirements
- Duration and dependencies
2) Unit Cost Modeling
Attach costs per unit:
- Labor: role-based hourly or monthly rates
- Materials: quantity x price
- Infrastructure: cloud usage, hardware
- External services: contractors, vendors
3) Revenue Modeling
Build revenue from:
- Units sold x price
- Contract values and timelines
- Subscription tiers and churn
- Conversion funnel estimates
4) Aggregation
Produce:
- Project budget by phase
- Monthly burn and runway
- Break-even timing
- Profit and loss summary
5) Multi-Currency Handling
Plans may involve multiple currencies (e.g., cross-border projects). The bottom-up model should:
- Track line items in native currency at the work-package level.
- Roll up to a reporting currency with explicit FX assumptions.
- Support a third currency when local currencies are unstable.
Reconciliation Layer
Compare bottom-up vs top-down outputs:
- Total revenue variance
- Margin variance
- Capex and opex mismatches
- Timeline inconsistencies
Reconciliation output:
- Variance report
- Recommended adjustments
- Updated confidence levels
Output Schema
{
"bottom_up": {
"total_cost": 2200000,
"total_revenue": 4800000,
"burn_rate_monthly": 180000,
"reporting_currency": "USD",
"fx_assumptions": [
{"pair": "BRL/USD", "rate": 0.19, "as_of": "2026-02-10", "volatility": "high"}
]
},
"top_down": {
"total_cost": 1500000,
"total_revenue": 5200000
},
"variance": {
"cost_delta": 700000,
"revenue_delta": -400000
},
"reconciliation_notes": [
"Bottom-up assumes 12 engineers, top-down assumes 8",
"Top-down margin range exceeds observed unit economics"
]
}
Integration Points
- Uses CBS generation as input for cost categories.
- Feeds into investor thesis matching and risk scoring.
- Drives evidence-based adjustments in financial claims.
Success Metrics
- Percentage of plans with bottom-up models.
- Reduction in financial variance after reconciliation.
- Investor confidence in financial projections.
Risks
- High data requirements: mitigate with default benchmarks and missing info prompts.
- Estimation complexity: prioritize major cost drivers first.
- False precision: publish ranges and confidence scores.
Future Enhancements
- Automated cost libraries by region and sector.
- Sensitivity analysis and scenario modeling.
- Learning system that updates estimates from real outcomes.
Detailed Implementation Plan
1) Bottom-up estimator architecture
For each WBS task, build a cost object: - labor profile (roles, hours, rates) - material BOM (qty × unit cost) - external services - fixed/variable overhead - contingency allocation
Aggregate task costs -> work package -> phase -> plan total.
2) Revenue build-up layer
For plans with revenue: - unit sales model or contract milestone model - churn/renewal assumptions (if subscription) - conversion and ramp assumptions
Link revenue timing to project timeline for cashflow realism.
3) Reconciliation algorithm (top-down vs bottom-up)
Input: - top-down scenario bands (P10/P50/P90) - bottom-up deterministic/ranged total
Compute variance decomposition by category: - labor delta - materials delta - capex delta - schedule-induced delta
Generate reconciliation recommendations ranked by expected impact.
4) Convergence rules
Define explicit convergence status:
- green: variance <= 10%
- yellow: 10–20%
- red: >20%
If yellow/red, require iteration actions before “finance-ready” status.
5) Iteration loop
- identify highest variance categories
- request missing inputs or benchmark corrections
- update assumptions
- recompute both models
- re-evaluate convergence state
Track each iteration for audit.
6) Integration points
- Pull CBS line items from Proposal 33
- Pull benchmark priors from Proposal 34
- Expose convergence status in plan summary
- Feed risk module when persistent red variance remains
7) Output package
Produce a finance bundle: - bottom-up ledger - top-down summary - variance decomposition chart - reconciliation action log - convergence status + signoff checklist
8) Rollout phases
- Phase A: deterministic bottom-up + simple variance
- Phase B: ranged bottom-up with confidence levels
- Phase C: automated reconciliation recommendations
- Phase D: closed-loop learning from actual spend/revenue outcomes
9) Validation checklist
- Accounting consistency (totals match component sums)
- Reproducibility under fixed assumptions
- Reviewer confidence uplift after reconciliation
- Reduced forecast error on executed projects
Detailed Implementation Plan (Convergence Operations)
Convergence Workflow
- Generate bottom-up ledger from WBS/CBS.
- Pull top-down baseline from proposal 34 module.
- Compute variance by category and timeline bucket.
- Trigger correction cycle until convergence status reaches green/yellow threshold.
Action Prioritization
- Rank correction actions by expected variance reduction per effort unit.
- Recommend max 5 actions per cycle to avoid analysis overload.
Signoff Policy
- Red variance blocks investor-ready status.
- Yellow requires explicit financial waiver.
- Green auto-advances to packaging phase.
Learning Loop
- Persist convergence trajectories to improve future default assumptions.