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Cost Basis Rebuilder

Reconstruct the numbers when the broker does not

Rebuilds missing or suspect cost basis after transfers, broken imports, or inconsistent historical records so tax reporting is not a guessing game.

CommunitySubmitted by CommunityPersonal10 min

INGREDIENTS

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PROMPT

Create a skill called "Cost Basis Rebuilder". Help me rebuild cost basis when broker data is missing or wrong after a transfer. Give me a chronological reconstruction workflow, discrepancy checklist, and a support-ready summary I can send if the broker needs to make corrections.

How It Works

This recipe is for missing, delayed, or obviously wrong cost basis data,

especially after ACATS/TOA transfers.

Triggers

  • Transfer completed but basis is missing or zero
  • Basis looks wrong after ACATS/TOA
  • Historical lots are incomplete

Inputs

  • Statements
  • Trade confirms
  • Existing basis shown by receiving broker
  • Transfer timeline

Outputs

  • Reconstruction checklist
  • Lot-by-lot basis worksheet
  • Missing-data list
  • Escalation packet for broker correction

Steps / Actions

  1. Gather all historical evidence.
  2. Reconstruct lots chronologically.
  3. Compare with receiving broker data.
  4. Flag discrepancies.
  5. Produce an escalation-friendly summary.

Failure Modes

  • Missing trade confirms that predate online access
  • Corporate actions (splits, mergers) not accounted for
Tags:#cost-basis#transfers#taxes#reconciliation