Tax Compliance Auditing

Precision audits for
Illinois auto dealerships.

Cynor Systems provides comprehensive tax compliance auditing services for the Illinois Secretary of State. We identify discrepancies, recover lost revenue, and ensure every transaction is properly reported.

ST-556

Tax Returns

Police Books

Inventory Records

Contracts

Finance & Sale

Odometer

Disclosure Statements

What we do

Full-scope tax compliance auditing for the state's largest revenue source.

01

On-Site Document Review

Our field auditors visit dealerships to examine police books, ST-556 tax returns, finance contracts, bills of sale, and odometer disclosures. Every transaction is accounted for.

02

AI-Accelerated Extraction

Proprietary document intelligence captures handwritten and printed data from scanned records with high accuracy, eliminating manual data entry and reducing audit cycle time.

03

Tax Rate Verification

Extracted amounts are automatically cross-referenced against Illinois DOR tax rates by ZIP code and transaction date, surfacing underpayments and calculation errors.

Why Cynor Systems

Technology-driven auditing that protects state revenue.

Faster Audit Cycles

Automated document capture and data extraction reduce per-dealership audit time by eliminating hours of manual transcription.

Higher Accuracy

Machine extraction removes human transcription errors. Every field is verified against structured schemas before analysis.

Comprehensive Coverage

Cross-referencing police book records against filed tax returns ensures no transaction goes unaudited. Missing filings are identified automatically.

Reduced Revenue Leakage

Systematic rate verification against IL DOR tables by ZIP code and date catches even minor discrepancies that compound across thousands of transactions.

Audit scope

Five document types. Every transaction verified.

ST-556

Vehicle Use Tax Transaction Return

The primary Illinois tax filing for each vehicle sale. We verify seller and buyer information, vehicle details, trade-in credits, tax rate application, and computed tax amounts.

Police Book

Record of Used Motor Vehicles

The dealer’s mandatory vehicle inventory ledger. We scan every page — purchased and sold sides — to reconstruct a complete transaction history and cross-reference against filed returns.

Finance Contract

Retail Installment Contract

Financing terms including cash price, trade-in allowance, amount financed, APR, and payment schedule. Compared against reported sale prices for consistency.

Bill of Sale

Cash Purchase Contract

Records the vehicle price, fees, and total balance due for cash transactions. We verify that reported tax amounts match the applicable rate for the buyer’s jurisdiction.

VD-303

Odometer Disclosure Statement

Certifies actual vehicle mileage at time of sale. We cross-reference odometer readings against police book entries and finance contracts for consistency.