Key Takeaways
- Start MLS searches tight and expand systematically: time first, then geography, then size range.
- Only sold listings are valid comps; active listings serve as ceiling checks.
- Verify MLS sold prices against county deed records to catch errors and undisclosed concessions.
- Build and reuse a standardized comp sheet template for consistency across analyses.
Effective comp analysis requires access to reliable sales data. This lesson covers the primary tools investors use to research comparable sales, the differences between sold, active, and pending listings, and how to verify transaction data for accuracy.
MLS Search Strategies
The MLS is the primary source for comp data, but effective searching requires strategy. Start with a tight search: same subdivision or neighborhood, ±15% of subject GLA, sold in last 6 months. If results are too few (under 3), expand one parameter at a time in this order: extend time to 12 months, then widen geographic area by 0.5 miles, then broaden size range to ±25%. This systematic expansion ensures you exhaust the best comps before accepting weaker ones. Pay attention to MLS data fields beyond price: days on market (DOM) reveals demand pressure, listing-to-sold price ratio indicates negotiation patterns, seller concessions affect the effective sale price, and agent remarks may disclose unusual circumstances (estate sale, relocation, investor purchase).
Why it matters: A property that sold for $350,000 with $10,000 in seller-paid closing costs has an effective sale price of $340,000. Always check for seller concessions in MLS data and adjust the comp's sale price accordingly before using it in your analysis.
Sold vs Active vs Pending Listings
Only sold listings are true comps for valuation—they represent completed, arm's-length transactions at verified prices. Active listings represent the upper limit of what sellers hope to achieve but not what buyers will actually pay. The spread between active listing prices and recent sold prices indicates market conditions: a wide spread suggests a buyer's market, a narrow spread suggests a seller's market. Pending listings provide a forward-looking indicator of where values are heading but the final sold price is not yet available. Use active listings as a ceiling check and pending listings as a directional indicator, but base your valuation on sold data.
Why it matters: Understanding this concept is essential for making informed investment decisions.
Public Record Verification and Comp Sheet Templates
Always verify MLS sold prices against county deed records. In disclosure states, the transfer tax amount on the deed reveals the actual transaction price (transfer tax ÷ tax rate = price). This verification catches MLS data entry errors, undisclosed concessions, and transactions that may have included personal property. PropStream ($99/month) aggregates MLS, county records, and foreclosure data into a single platform designed for investors. Redfin provides free access to recent sold data with MLS photos and transaction details in most markets. Build a reusable comp sheet template in a spreadsheet: property details (address, size, age, condition), sale information (date, price, DOM, concessions), adjustment grid, and adjusted value. Using the same template for every analysis ensures consistency and creates a searchable archive of your comp research.
| Tool | Data Type | Cost | Investor Utility |
|---|---|---|---|
| MLS (via agent) | Sold, active, pending | Agent access | Gold standard for residential comps |
| County Records | Deeds, assessments | Free | Verification, off-market discoveries |
| PropStream | Aggregated investor data | $99/mo | All-in-one comp, owner, mortgage data |
| Redfin | Sold, estimates | Free | Good accuracy in Redfin-active markets |
| Zillow | Estimates, sold | Free | Broad coverage, lower accuracy off-market |
Comp research tools comparison for investors
Why it matters: Understanding this concept is essential for making informed investment decisions.
Key Takeaways
- ✓Start MLS searches tight and expand systematically: time first, then geography, then size range.
- ✓Only sold listings are valid comps; active listings serve as ceiling checks.
- ✓Verify MLS sold prices against county deed records to catch errors and undisclosed concessions.
- ✓Build and reuse a standardized comp sheet template for consistency across analyses.
Sources
- Appraisal Institute — Sales Comparison Methods(2025-03-15)
- Fannie Mae — Appraisal Guidelines(2025-03-15)
Common Mistakes to Avoid
Selecting comparable properties based on price proximity to a desired value rather than true similarity.
Consequence: Circular reasoning confirms a predetermined conclusion instead of independently estimating market value.
Correction: Select comps based on physical and locational similarity, not on how close their prices are to your target.
Failing to adjust for differences in transaction conditions between comparable sales.
Consequence: Non-arm's-length sales, seller concessions, and financing terms can distort the comp set by 5-15%.
Correction: Verify transaction type and terms for all comps and make appropriate adjustments.
Test Your Knowledge
1.In Comp Research Tools and Data Access, what determines the reliability of a comparable sale?
2.What is the maximum recommended net adjustment for a single comparable sale?
3.How should the final value be determined from multiple adjusted comparable sales?