Comparable Analysis: How to Determine What a Seattle Home Is Really Worth

Master comparable analysis using real Seattle market data: learn to select, adjust, and interpret comp sales to make informed offers and avoid overpaying.

Tags:comps, pricing, market-analysis, washington, seattle, valuation
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The house is listed at $875,000. Is that a good price? Overpriced? A steal?

You can't know without comparing it to similar homes that recently sold. This is called comparable analysis (or "comps"), and it's how appraisers, agents, and smart buyers determine fair market value. In Seattle's varied market, a house in Ballard and a house in Beacon Hill can't be compared directly, even if they're the same size.

In this article, you'll learn where to find comparable sales data (free tools), how to select truly comparable homes, how to adjust for differences (view, condition, parking), Seattle micro-market considerations, how to align your offer with appraisal expectations, and see a real comparable analysis example with calculations.

Table of Contents

Why Comparable Analysis Matters

Three Key Uses

1. Determine fair offer price:

  • Avoid overpaying
  • Make competitive but reasonable offer
  • Justify your offer to seller

2. Predict appraisal value:

  • Lender requires appraisal
  • Appraisal must support purchase price
  • Low appraisal kills deals or requires more cash

3. Negotiate with confidence:

  • Back up your offer with data
  • Counter seller's expectations
  • Show you've done homework

What Appraisers Look For

Appraisers use comps to determine value:

  • Recent sales (last 3-6 months)
  • Similar homes (size, age, condition)
  • Same neighborhood (or very close)
  • Adjust for differences

Your goal: Make offer that appraisal will support

Seattle reality: In hot market, appraisals sometimes lag behind rapid price increases. In slow market, appraisals may come in low if prices declining.

Where to Find Comparable Sales

Free Public Tools

Redfin (Best for buyers):

  • Website: redfin.com
  • Shows: sold prices, sale dates, days on market
  • Filter: by neighborhood, price range, size, sold date
  • Advantage: Most user-friendly, detailed data

How to use Redfin:

  1. Search address of home you're considering
  2. Click "Nearby Homes"
  3. Filter: "Sold" in last 3-6 months
  4. Sort by: similar size, same property type
  5. Click each comp to see details

Zillow:

  • Website: zillow.com
  • Shows: sold prices, Zestimate history
  • Filter: similar to Redfin
  • Advantage: Zestimate provides estimate (take with grain of salt)

How to use Zillow:

  1. Search address
  2. Scroll to "Nearby comparable sales"
  3. Filter by sold date, size, type
  4. Review details of each comp

King County Parcel Viewer:

  • Website: kingcounty.gov/services/gis/Maps/parcel-viewer
  • Shows: all sales with dates and prices
  • Advantage: Official county records
  • Disadvantage: Less user-friendly

Snohomish County Assessor:

  • Website: snohomish.county.property.info
  • Shows: sales data for Snohomish County
  • Use for: Lynnwood, Everett, Bothell (north)

Pierce County Assessor:

  • Website: atip.piercecountywa.gov
  • Shows: sales data for Pierce County
  • Use for: Tacoma, Puyallup, Lakewood

What Your Agent Can Provide

NWMLS (Northwest Multiple Listing Service):

  • Access: Real estate agents only
  • Shows: detailed listing info, days on market, price changes
  • Advantage: Most comprehensive data
  • Your agent can pull comps report for you

What to ask your agent for:

  • Comps report (3-6 recent sales)
  • Active listings (competition)
  • Pending sales (market direction)
  • Price per square foot analysis

Selecting Comparable Homes

The 3-6 Month Rule

Ideal timeframe: Last 3 months

  • Most recent = most relevant
  • Reflects current market
  • What appraisers prefer

Acceptable: Last 6 months

  • If not enough recent sales
  • Adjust for market trends
  • Note if market changed

Avoid: Older than 6 months

  • Market may have shifted
  • Appraisers won't use
  • Not reliable

Seattle example:

  • Spring 2024: prices rising 5% in 3 months
  • Using 6-month-old comps = undervaluing
  • Fall 2024: prices flat
  • 6-month-old comps = still relevant

Geographic Boundaries

Same neighborhood (best):

  • Within 0.5 miles ideal
  • Same school boundaries
  • Similar character and amenities

Adjacent neighborhood (acceptable):

  • If not enough comps in same area
  • Similar price range and character
  • Note differences

Different neighborhood (avoid):

  • Seattle micro-markets vary significantly
  • Ballard ≠ Beacon Hill
  • Capitol Hill ≠ Columbia City
  • Not comparable even if similar homes

Seattle micro-market examples:

Queen Anne:

  • Lower Queen Anne: urban, walkable, $600-700/sqft
  • Upper Queen Anne: residential, views, $700-800/sqft
  • Can't compare directly despite same neighborhood name

Eastside:

  • Downtown Bellevue: high-rise condos, $800-1000/sqft
  • Bellevue suburbs: single-family, $600-700/sqft
  • Very different markets

Property Characteristics

Must match:

  • Property type (SFH, condo, townhome)
  • Bedrooms (within 1)
  • Bathrooms (within 1)
  • Square footage (within 20%)
  • Lot size (within 30% for SFH)

Should match:

  • Age (within 10-20 years)
  • Condition (similar updates)
  • Style (ranch, two-story, split-level)
  • Garage/parking

Nice to match:

  • View
  • Finishes
  • Amenities
  • Basement

Example - good comp:

  • Subject: 1,800 sqft, 3 bed, 2 bath, built 1960, Ballard
  • Comp: 1,750 sqft, 3 bed, 2 bath, built 1965, Ballard
  • Match: ✅ Very comparable

Example - bad comp:

  • Subject: 1,800 sqft, 3 bed, 2 bath, built 1960, Ballard
  • Comp: 2,400 sqft, 4 bed, 3 bath, built 2020, Fremont
  • Match: ❌ Not comparable (size, age, location all different)

Making Adjustments

Why Adjustments Are Needed

No two homes are identical:

  • Different views
  • Different condition
  • Different features
  • Different locations (even within neighborhood)

Adjustments account for differences:

  • Add value for superior features
  • Subtract value for inferior features
  • Arrive at adjusted comparable value

Common Adjustments

Square footage:

  • Most important adjustment
  • Calculate: price per square foot
  • Apply to subject property

Example:

  • Comp: 1,600 sqft, sold $800,000 = $500/sqft
  • Subject: 1,800 sqft
  • Estimated value: 1,800 × $500 = $900,000

Bedrooms/bathrooms:

  • Extra bedroom: +$20,000-$40,000
  • Extra bathroom: +$15,000-$30,000
  • Seattle varies by neighborhood

Garage/parking:

  • Garage vs no garage: +$30,000-$50,000
  • Extra parking space: +$10,000-$20,000
  • Downtown Seattle: parking worth more

Condition:

  • Updated vs dated: +$30,000-$100,000
  • Depends on extent of updates
  • Kitchen and bathrooms most important

View:

  • Water view: +$100,000-$500,000+ (depends on quality)
  • Mountain view: +$50,000-$150,000
  • City view: +$30,000-$100,000
  • No view: baseline

Lot size (for SFH):

  • Larger lot: +$50-$150 per sqft of extra land
  • Seattle: land is expensive
  • Eastside: even more expensive

Basement:

  • Finished basement: +$50-$100/sqft
  • Unfinished: +$20-$40/sqft
  • Daylight basement: worth more

Age and updates:

  • Newer home: +$10,000-$50,000
  • Recent remodel: +$50,000-$150,000
  • Depends on scope

Seattle-Specific Adjustments

Proximity to light rail:

  • Within walking distance (0.5 mile): +$30,000-$80,000
  • Varies by station and neighborhood
  • More valuable in urban areas

School district:

  • Top-rated schools: +10-20% premium
  • Bellevue SD, Lake Washington SD, Northshore SD
  • Verify boundaries (can change)

Walkability:

  • Walk Score 90+: +$20,000-$60,000
  • Depends on buyer preferences
  • More valuable to some buyers

ADU (Accessory Dwelling Unit):

  • Existing ADU: +$100,000-$200,000
  • Rental income potential
  • ADU-ready lot: +$20,000-$50,000

Real Comparable Analysis Example

Subject Property

Address: 123 Example St, Ballard, Seattle
Type: Single-family home
Size: 1,800 sqft
Bedrooms: 3
Bathrooms: 2
Built: 1960
Lot: 5,000 sqft
Condition: Good (updated kitchen, original bathrooms)
Garage: 1-car detached
View: None
List price: $875,000

Comparable Sales (Last 3 Months)

Comp 1:

  • Address: 456 Nearby St, Ballard
  • Sold: $850,000 (2 months ago)
  • Size: 1,750 sqft
  • Bed/Bath: 3/2
  • Built: 1955
  • Lot: 4,800 sqft
  • Condition: Good (similar updates)
  • Garage: 1-car detached
  • View: None

Comp 2:

  • Address: 789 Close Ave, Ballard
  • Sold: $920,000 (1 month ago)
  • Size: 2,000 sqft
  • Bed/Bath: 3/2.5
  • Built: 1965
  • Lot: 5,200 sqft
  • Condition: Excellent (fully remodeled)
  • Garage: 2-car attached
  • View: Partial water view

Comp 3:

  • Address: 321 Around Pl, Ballard
  • Sold: $825,000 (3 months ago)
  • Size: 1,700 sqft
  • Bed/Bath: 3/1.5
  • Built: 1958
  • Lot: 4,500 sqft
  • Condition: Fair (needs updates)
  • Garage: None
  • View: None

Adjustment Analysis

Comp 1 Adjustments:

  • Base price: $850,000
  • Size adjustment: +50 sqft × $500/sqft = +$25,000
  • Lot adjustment: +200 sqft × $100/sqft = +$20,000
  • Adjusted value: $895,000

Comp 2 Adjustments:

  • Base price: $920,000
  • Size adjustment: -200 sqft × $500/sqft = -$100,000
  • Bathroom adjustment: -0.5 bath × $20,000 = -$10,000
  • Condition adjustment: -$50,000 (subject not fully remodeled)
  • Garage adjustment: -$30,000 (subject has 1-car, comp has 2-car)
  • View adjustment: -$50,000 (subject no view)
  • Adjusted value: $680,000

Comp 3 Adjustments:

  • Base price: $825,000
  • Size adjustment: +100 sqft × $500/sqft = +$50,000
  • Bathroom adjustment: +0.5 bath × $20,000 = +$10,000
  • Lot adjustment: +500 sqft × $100/sqft = +$50,000
  • Condition adjustment: +$30,000 (subject better condition)
  • Garage adjustment: +$40,000 (subject has garage)
  • Adjusted value: $1,005,000

Conclusion

Adjusted comparable values:

  • Comp 1: $895,000
  • Comp 2: $680,000 (outlier - too many differences)
  • Comp 3: $1,005,000

Average (excluding outlier): ($895,000 + $1,005,000) / 2 = $950,000

Estimated fair market value: $920,000-$950,000

List price: $875,000

Analysis: Home is priced below market value. Likely to receive multiple offers. Consider offering $920,000-$950,000 depending on competition.

Appraisal Alignment Strategy

Why Appraisal Matters

Lender requires appraisal:

  • Protects lender's investment
  • Must support purchase price
  • Ordered after offer accepted

If appraisal comes in low:

  • Lender won't loan full amount
  • You need more cash down
  • Or renegotiate price
  • Or walk away

Example:

  • Offer: $950,000
  • Appraisal: $900,000
  • Gap: $50,000
  • You need extra $50,000 cash or renegotiate

How to Avoid Low Appraisal

1. Use recent comps (last 3 months):

  • What appraisers will use
  • Most relevant data

2. Stay within 5% of comps:

  • Appraisers have less flexibility
  • Easier to justify value

3. Include comp analysis with offer:

  • Show seller you've done homework
  • Helps appraiser find same comps
  • Demonstrates reasonable offer

4. Consider appraisal gap coverage:

  • Offer to cover gap up to certain amount
  • Example: "Will cover appraisal gap up to $25,000"
  • Makes offer stronger
  • But costs you cash if appraisal low

5. Order pre-appraisal (rare):

  • Pay for appraisal before offer
  • Know value in advance
  • Costs $500-$700
  • Only in very competitive situations

Seattle Appraisal Challenges

Rapid price increases:

  • Comps lag behind current market
  • Appraisals may come in low
  • More common in hot market (spring)

Unique properties:

  • Hard to find true comps
  • Appraisers have to go farther afield
  • More subjective

Micro-market variations:

  • Appraiser must understand local market
  • Queen Anne vs Ballard vs Capitol Hill
  • Experience matters

New construction:

  • Easier to appraise (other new homes)
  • Less variation
  • Fewer surprises

When Comps Don't Tell Whole Story

Limitations of Comparable Analysis

Unique features:

  • One-of-a-kind home
  • Exceptional view
  • Historic property
  • Hard to quantify value

Market momentum:

  • Rapidly rising market
  • Comps lag behind
  • Current demand higher than comps suggest

Emotional value:

  • Perfect for your needs
  • Dream home
  • Worth more to you than market

Competition:

  • Multiple offers expected
  • Comps show past, not current demand
  • May need to exceed comps to win

Other Valuation Factors

Days on market:

  • Under 7 days: high demand, expect over asking
  • 7-30 days: normal market
  • Over 30 days: low demand, negotiate below asking

Price reductions:

  • Multiple reductions: seller motivated
  • Room to negotiate below comps

Seller motivation:

  • Job transfer, divorce, financial stress
  • May accept below market value
  • Ask agent about situation

Condition and updates:

  • Move-in ready worth premium
  • Needs work worth discount
  • Adjust comps accordingly

Future potential:

  • ADU-ready lot
  • Expansion possibilities
  • Neighborhood improving
  • Worth more than comps suggest

Common Mistakes to Avoid

Selection Errors

Cherry-picking comps:

  • Mistake: Only selecting favorable comparables
  • Impact: Unrealistic price expectations
  • Solution: Use all relevant comps objectively

Ignoring condition differences:

  • Mistake: Not adjusting for property condition
  • Impact: Inaccurate value estimates
  • Solution: Make appropriate condition adjustments

Geographic mismatch:

  • Mistake: Using comps from different markets
  • Impact: Inaccurate value estimates
  • Solution: Focus on same neighborhood

Using outdated comps:

  • Mistake: Using sales older than 6 months
  • Impact: Inaccurate value estimates
  • Solution: Use recent sales with time adjustments

Adjustment Errors

Over-adjusting:

  • Mistake: Making too many or too large adjustments
  • Impact: Unreliable value estimates
  • Solution: Limit adjustments to significant differences

Under-adjusting:

  • Mistake: Not accounting for important differences
  • Impact: Inaccurate value estimates
  • Solution: Identify and adjust for all significant differences

Inconsistent methodology:

  • Mistake: Using different approaches for similar items
  • Impact: Unreliable analysis
  • Solution: Use consistent adjustment methods

Data Quality Issues

Single source reliance:

  • Mistake: Using only one data source
  • Impact: Incomplete or inaccurate information
  • Solution: Cross-reference multiple sources

Unverified information:

  • Mistake: Not checking data accuracy
  • Impact: Unreliable analysis
  • Solution: Verify all data with primary sources

Summary

Key takeaways:

  • Use Redfin or Zillow to find comparable sales (last 3-6 months)
  • Select comps: same neighborhood, similar size, same property type
  • Adjust for differences: size, condition, view, parking, features
  • Calculate price per square foot as baseline
  • Seattle micro-markets vary significantly (can't compare across neighborhoods)
  • Align offer with appraisal expectations (within 5% of comps)
  • Consider market momentum and competition (comps show past, not current demand)
  • Your agent can provide detailed NWMLS comps report

Next steps:

  1. Find 3-5 comparable sales for home you're considering
  2. Create comparison spreadsheet with adjustments
  3. Calculate estimated value range based on adjusted comps
  4. Discuss with your agent to verify analysis
  5. Determine offer price based on comps, competition, and your budget
  6. Include comp analysis with your offer to show you've done homework

This article provides general information about comparable analysis and should not be considered professional appraisal advice. Consult with your real estate agent or a licensed appraiser for guidance specific to your situation.

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