Comparable Sales
Sales should be relevant to the subject property and supported by appropriate market analysis and adjustments.
Income Evidence
Income-producing properties may require support for rents, expenses, vacancy, capitalization rates and operating history.
Appraisal Analysis
The appraisal should present a consistent methodology, credible market evidence and a logical reconciliation.
The Cook County Board of Review places significant emphasis on the quality, organization, and credibility of valuation evidence submitted during a property tax appeal. In many cases, appeals are weakened not by the overall argument itself, but by unsupported assumptions, incomplete documentation, or improperly presented appraisal evidence.
For attorneys handling commercial and multi-family property tax appeals, understanding how valuation evidence is reviewed can materially impact the strength of an appeal.
Comparable Sales Selection Matters
One of the most common weaknesses in Board of Review and PTAB valuation evidence is the selection of comparable sales that differ significantly from the subject property in:
- Gross building area
- Unit count
- Unit mix
- Age and condition
- Location
- Land-to-building ratio
- Occupancy characteristics
While adjustments may account for certain differences, excessive variation between the subject and comparable properties can reduce the reliability of the analysis.
Particular scrutiny is often placed on:
- Large adjustments
- Unsupported market condition adjustments
- Inconsistent capitalization rates
- Sales occurring outside the relevant assessment period
- Reliance on distressed or non-arm’s-length transactions
Income and Expense Documentation
For income-producing properties, the Board generally expects property-specific financial evidence rather than generalized market assumptions.
Important supporting documentation may include:
- Historical operating statements
- Current rent rolls
- Lease summaries
- Vacancy history
- Capital expenditure history
- Real estate tax history
- Market leasing data
Rent rolls should generally reflect records maintained in the ordinary course of business rather than attorney-prepared summaries.
Appraisal Report Quality
Appraisals submitted in support of tax appeals should present:
- Clear adjustment support
- Consistent methodology
- Credible market evidence
- Logical reconciliation
- USPAP compliance
Particular attention is often given to:
- Comparable selection
- Highest and best use conclusions
- Vacancy assumptions
- Capitalization rate support
- Treatment of real estate taxes
- Internal consistency between approaches
Reports containing unsupported adjustments or inconsistent conclusions may receive reduced evidentiary weight.
Vacancy and Collection Loss Support
Generalized vacancy assumptions may carry limited persuasive value without property-specific evidence.
Support for elevated vacancy claims may include:
- Historical occupancy trends
- Leasing history
- Marketing efforts
- Tenant rollover exposure
- Deferred maintenance issues
- Market absorption conditions
For distressed occupancy situations, evidence demonstrating the cause and duration of vacancy can become particularly important.
Practical Considerations for Attorneys
Strong valuation evidence is typically:
- Well organized
- Internally consistent
- Market supported
- Property specific
- Easy for reviewing bodies to follow
In many appeals, clarity and credibility can be just as important as the valuation conclusion itself.
Related Cook County Property Tax Appeal Resources
Attorney Pre-Hearing Appraisal Evidence Checklist → Commercial Property Tax Appeal Appraisals by David Barros, MAI →Need an Appraisal for a Cook County Property Tax Appeal?
David Barros, MAI provides commercial real estate appraisal services for Cook County property tax appeals, including valuation analysis, appraisal review, Board of Review support and PTAB litigation support.
Contact David Barros, MAIThis article is provided for general informational purposes and is not legal advice or a substitute for reviewing the applicable Cook County Board of Review, Illinois Property Tax Appeal Board, or other governing requirements applicable to a particular appeal.