Written by Russell Harrist
Colorado Certified Residential Appraiser · Certified Probate Expert (CPE) · 25 Years of Experience
Published August 4, 2026
Three different tools can estimate a property's value. They are not interchangeable. Here is what each one is, what it's good for, and when a USPAP-compliant appraisal is required.
An Automated Valuation Model (AVM) is a computer-generated estimate based on publicly available data, such as comparable sales in public records, tax assessments, and market trends. The most widely recognized example is Zillow’s “Zestimate.”
What AVMs are good for: Getting a quick, general sense of a property’s approximate value before deciding whether to order a formal appraisal. They are fast, free, and require no human involvement.
What AVMs cannot do: AVMs cannot see inside the property. They cannot account for interior condition, recent improvements, unique features, or anything not reflected in public data. Accuracy varies significantly by market area, property type, and data availability. In some markets, AVMs are frequently off by 10-20% or more.
AVMs are not accepted by Colorado probate courts or the IRS as documentation of fair market value for estate purposes. Great Estates provides a free AVM report as a helpful starting point for personal representatives, but a full appraisal is required for legal and tax purposes.
A Broker Price Opinion (BPO) is a market analysis prepared by a licensed real estate broker. Great Estates’ BPO uses appraisal-style methodology (detailed comparable selection and market-supported adjustments), making it more rigorous than a typical drive-by BPO or informal agent opinion.
What a BPO is good for: A cost-effective market analysis when a full USPAP appraisal is not required, or as a preliminary value estimate before deciding whether to order a full appraisal. Available from Great Estates for $225.
What a BPO is not: A BPO is not a formal appraisal. It is not prepared under professional appraisal standards (USPAP) in the role of a certified appraiser, and it does not include a signed appraisal certification. It is a market analysis, not a certified opinion of value.
A BPO is not accepted by Colorado probate courts or the IRS as documentation of fair market value. Even a detailed, appraisal-style BPO does not meet the legal standard for probate court filings or IRS estate tax purposes; a full USPAP appraisal is required for those.
A USPAP-compliant appraisal is a formal written opinion of value prepared by a state-certified or state-licensed appraiser in accordance with the Uniform Standards of Professional Appraisal Practice. It includes a signed certification, stated scope of work, limiting conditions, and market analysis appropriate to the assignment type.
For date of death assignments, the appraisal is prepared using retrospective methodology: the effective date is anchored to the date of death, and all analysis reflects market conditions as of that date.
A USPAP-compliant appraisal is required when:
| Criteria | AVM | BPO | USPAP Appraisal |
|---|---|---|---|
| Typical cost | Free | $225 | $350–$550 |
| Prepared by | Computer algorithm | Licensed real estate broker | State-certified appraiser |
| Includes interior inspection | No | Yes | Yes (full scope) |
| Signed certification | No | No | Yes |
| USPAP-compliant | No | No | Yes |
| Accepted for probate court | No | No | Yes |
| Accepted for IRS filing | No | No | Yes |
| Establishes stepped-up basis | No | No | Yes |
Great Estates offers a free AVM report as a starting point. For estate purposes, a USPAP-compliant appraisal is required.
Great Estates, Inc. provides full interior/exterior and exterior-only appraisals for Colorado estate purposes. Order online in two minutes or start with a free AVM estimate.