What Is a Comparative Market Analysis (CMA)? CMA vs Appraisal
A comparative market analysis (CMA) is a real estate agent’s estimate of the price a home is likely to sell for, built from recently sold, pending and active homes that compete with it and adjusted for the differences between them. It is not an appraisal: California law says an opinion of value from a real estate licensee “shall not be referred to as an appraisal.” An online estimate such as a Zestimate is a third thing, an automated model that never sees the inside of the house.
A CMA is the tool most sellers use to set a list price and most buyers use to decide what to offer. It’s only as good as the comparables chosen and the reasoning behind each adjustment, which is where unusual North Bay properties (acreage, wells, ADUs, vines, views) trip up quick estimates. This guide explains how a CMA is built, how it differs from an appraisal, and walks through a labeled hypothetical example. It is part of our home-selling process guides.
What goes into a CMA
A useful CMA starts with an accurate description of the subject property and then finds the homes a buyer would realistically compare it with.
- Property facts: legal lot size, finished living area, bedrooms and baths, year built, garage and parking, and any second unit.
- Condition and updates: roof, systems, kitchen and baths, and whether work was permitted.
- Site and setting: view, slope, usable flat land, road frontage, privacy, and outbuildings.
- Utilities: public water and sewer or a well and septic system.
- Constraints: fire or flood zone, easements, HOA rules, and anything that affects insurance or financing.
- Market data: closed sales, pending sales, active listings and listings that expired or were withdrawn, plus how long they took and any price changes.
The agent then narrows the data to the closest matches, adjusts each one for its differences, and reconciles the results into a price range. Our market insights page shows the broader trends that sit behind those choices.
Sold, pending, active and expired: what each comp tells you
| Type of comparable | What it shows | Limits |
|---|---|---|
| Closed sale | What a buyer actually paid and a lender financed | Reflects the market when it went into contract, often weeks before closing |
| Pending sale | The most current evidence that a buyer agreed to a price | The final price usually isn’t public until it closes |
| Active listing | Your competition today and the prices buyers are weighing | An asking price is not a sale price |
| Expired or withdrawn listing | A price the market declined | The cause may be condition, marketing or the seller’s terms |
Appraisers working on loans sold to Fannie Mae must report at least three closed comparables and can use listings and contracts only as supporting data. Fannie Mae’s guide also says comparables closed within the last 12 months should be used, with older sales acceptable when the appraiser explains why they are used. A CMA isn’t bound by those rules, but a list price that ignores them can run into a low appraisal later, as our appraisal contingency guide explains.
How adjustments work
No two homes match, so each comparable is adjusted toward the subject. If a comp has something the subject lacks, its price is adjusted down; if it lacks something the subject has, its price is adjusted up.
The amount of each adjustment should come from the market, not a rule of thumb. Fannie Mae’s appraisal guidance says adjustments “must reflect the market’s reaction,” supported by evidence such as paired sales or price indices, and that it sets no fixed limit on net or gross adjustments. The same discipline makes a CMA credible.
Common adjustments in the North Bay include:
- Living area and lot size: rarely linear, especially on acreage, where each added acre often adds less than the one before.
- A second unit: a permitted ADU and an unpermitted studio are different assets; see our guides to buying a home with an ADU and selling with an unpermitted ADU.
- Water and wastewater: a well and septic system can add inspection and lending steps that buyers price in.
- Vines and agricultural improvements: a hobby block of vines is valued differently from a commercial vineyard; our vineyard valuation guide covers the commercial case.
- View, condition and location within the area: the adjustments buyers argue about most.
CMA, appraisal, automated estimate and BPO compared
| Comparative market analysis | Appraisal | Automated valuation (e.g., a Zestimate) | Broker price opinion | |
|---|---|---|---|---|
| Prepared by | A real estate agent or broker | A state-licensed or certified appraiser | A computer model | A real estate licensee, usually for a lender or asset manager |
| Main purpose | Setting a list price or an offer | Lending, estates, litigation and tax | A quick reference point | Default, REO and portfolio decisions |
| Standards | The agent’s professional judgment | USPAP and lender guidelines | The vendor’s model | The client’s form and instructions |
| Sees the property? | Usually, on a walkthrough | Yes, on most assignments | No | Exterior or interior, depending on the order |
USPAP, the Uniform Standards of Professional Appraisal Practice, is maintained by the Appraisal Standards Board of The Appraisal Foundation; the current edition is the 2024 edition. Under Business and Professions Code 11302, an opinion a real estate licensee gives in the ordinary course of business is excluded from the statute’s definition of an appraisal. Broker price opinions are covered in our guide to BPOs and REO valuation, and estate valuations in our page on date-of-death valuations.
A worked example (hypothetical)
This example is invented to show the method. The property, the comparables and every dollar amount are hypothetical; the adjustment figures are placeholders, not market rates for any Sonoma County area.
The subject is a 2,000-square-foot, three-bedroom single-level home on 5 acres in unincorporated Sonoma County, with a well, a septic system, about an acre of planted vines, a permitted 500-square-foot detached ADU and a dated kitchen. It sits in a High fire hazard severity zone.
| Comparable | Status and price | Key differences from the subject | Adjustments | Adjusted indication |
|---|---|---|---|---|
| A | Sold four months ago, $1,450,000 | 100 sq ft larger, 3 acres, no ADU | Size −$30,000; land +$40,000; ADU +$100,000 | $1,560,000 |
| B | Sold two months ago, $1,525,000 | 50 sq ft smaller, 6 acres, unpermitted studio; also on a well and septic | Size +$15,000; land −$20,000; permitted ADU +$60,000 | $1,580,000 |
| C | Pending, listed at $1,595,000 | Same size and acreage, permitted ADU, remodeled kitchen | Condition −$50,000 (if it closes at list) | $1,545,000 |
| D | Active 80 days at $1,695,000 after one reduction | Similar, with a pool | Not adjusted; used as a ceiling | Market resisting $1,695,000 |
The adjusted indications cluster between $1,545,000 and $1,580,000. Comp B gets the most weight because it is the most recent closed sale and shares the subject’s well and septic setup. Comp C is a strong signal but uncertain until it closes, and Comp D shows where buyers have stopped.
A seller might reasonably list within or just above that range depending on strategy, and a buyer would use the same grid to judge whether an offer above it can be supported if the lender’s appraisal comes in lower. Fire-zone insurance quotes would be checked before either side relies on the number.
Where North Bay CMAs go wrong
- Too few true comparables: rural and estate properties may have only a handful of sales a year. Fannie Mae’s guidance allows more distant comps for rural property if the reasons are explained, and a CMA should show the same reasoning.
- Price per square foot alone: it ignores land, second units and condition, and misleads most on acreage.
- Unpermitted space counted as living area: the record and the listing should agree, or the difference should be priced.
- Active listings treated as sales: asking prices show competition, not value.
- Insurance and financing ignored: a home that is hard to insure or finance draws fewer buyers.
- Stale data in a moving market: time adjustments need support, just as Fannie Mae requires of appraisers.
How to get a useful CMA
- Say what it’s for: listing, buying, a trust or estate decision, or refinancing plans each call for a different emphasis.
- Share records: permits, the ADU’s status, recent work, well and septic reports, and any pre-listing inspection.
- Ask to see the comps: every comparable, why it was chosen, and the support for each adjustment.
- Ask for a range, not one number: and what would move the price toward each end.
- Turn price into proceeds: run the range through a seller net sheet before choosing a list price.
Questions people ask
Is a CMA the same as an appraisal?
No. A CMA is an agent’s opinion of likely price. An appraisal is prepared by a licensed or certified appraiser under USPAP, and California law says a licensee’s opinion of value can’t be called an appraisal.
How accurate is a comparative market analysis?
It depends on how many truly similar recent sales exist and how well each adjustment is supported. In a subdivision with frequent sales the range can be narrow; on acreage, view or vineyard properties, judgment matters more and the range is wider.
How many comps should a CMA have?
There’s no legal minimum for a CMA. Appraisals for Fannie Mae loans require at least three closed sales, and a CMA built on fewer closed sales should explain why.
Why is my Zestimate different from my CMA?
An automated model works from public records and listing data without seeing the house, so it can miss condition, permitted improvements, a second unit or features of the land that a CMA adjusts for.
Does a CMA cost anything?
Agents usually prepare one at no charge when you’re considering selling or buying. An appraisal is a paid professional service.
Can a buyer use a CMA to make an offer?
Yes. Buyers’ agents prepare CMAs to judge an asking price and to anticipate whether the lender’s appraisal will support the offer.
If you’d like a CMA for your property, with every comp and adjustment shown, request one through our home valuation page or our property value request.
Sources & notes
- Justia (California Code): Business and Professions Code section 11302
- The Appraisal Foundation: Uniform Standards of Professional Appraisal Practice (USPAP)
- Fannie Mae Selling Guide B4-1.3-08: Comparable Sales (06/04/2025)
- Fannie Mae Selling Guide B4-1.3-09: Adjustments to Comparable Sales (06/04/2025)
Last reviewed October 2026 by Matthew Martinez.
