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    Property profile & analytics

    31 River Rd Cos Cob, CT 06807

    • Medical Office Space
    • 13,430 SF
    • 0.78 lot acres
    For Lease
    View listing
    Value Estimations
    Cap Rate Potential
    Location Intelligence
    Property ID
    US15-0343367
    The Realmo ID is a unique identifier assigned to every property, incorporating country codes and precise geo-coordinates for 300x300-foot land blocks. It enables standardized data collection and seamless integration of disparate sources such as ownership, tax, title data and physical specifications. By aggregating current and historical records, the Realmo ID powers advanced analytics and delivers deep, verifiable insights for real estate professionals.

    Current Use by Public Records

    • Harbor view / Medical Clinic
    • Goodwin Dental / Dental Office
    • Dr. Michael Mangonon, DO / Physician
    • Donna Hagberg, MD / Physician
    • Kevin Plancher, MD / Physician

    Property Details for 31 River Rd

    Year built
    1965
    Construction
    STEEL FRAME
    Lot size
    0.78 lot acres
    Property size
    13,430 SF
    Zone code
    WB
    Property type
    Medical Office Space
    Property subtype
    Medical centers
    APN
    GREE M:08 B:3142/S
    APU
    GREEM08B3142S

    Value Estimations

    based on Realmo’s proprietary methodology

    • Alternative Use

      Use
      Estimation
      MEDICAL BUILDING
      $1,040,000
      Current use
      AUTO REPAIR, GARAGE
      $1,355,000
      Change: +30% Conversion: Difficult
      COMMERCIAL (GENERAL)
      $1,325,000
      Change: +28% Conversion: Easy
      RETAIL STORES
      $1,215,000
      Change: +17% Conversion: Difficult
      APARTMENT HOUSE (5+ UNITS)
      $1,200,000
      Change: +16% Conversion: Moderate
      INDUSTRIAL (GENERAL)
      $850,000
      Change: -18% Conversion: Difficult

    Get a detailed, property-specific valuation — fast and free

    Location Insight

    • Map
    • Local Demand
    City
    Cos Cob
    County
    Fairfield
    State
    Connecticut
    Longitude
    -73.5949
    Latitude
    41.0359
    CBSA code
    14860
    CBSA name
    BRIDGEPORT-STAMFORD-NORWALK, CT METROPOLITAN STATISTICAL AREA

    Property Tax & Assessments

    Tax date
    Tax Amount
    Assessed Land Value
    Assessed Improvement Value
    Total Assessed Value
    Applied Tax Rate
    Land Market Value
    Improvement Market Value
    Total Market Value
    2023
    $62,816
    $1,739,290
    $3,659,110
    $5,398,400
    -
    $0.00
    $0.00
    $0.00

    Comparable in this City

    • Value Estimation
      $735,000
      8,000 SF

      12 Putnam Ave, Unit 40

      MEDICAL BUILDING • 8,000 SF
      12 Putnam Ave, Cos Cob, CT 06807
      View Details
    • Value Estimation by Request
      1,219 SF

      533 Putnam Ave

      MEDICAL BUILDING • 1,219 SF
      533 Putnam Ave, Cos Cob, CT 06807-2506
      View Details
    • Value Estimation by Request
      47,957 SF

      122-140 Putnam Ave

      Office properties & Spaces • 47,957 SF
      122-140 Putnam Ave, Greenwich, CT 06807
      View Details
    • Value Estimation by Request
      14,905 SF

      393-407 Putnam Ave

      Office properties & Spaces • 14,905 SF
      393-407 Putnam Ave, Greenwich, CT 06807
      View Details
    • Value Estimation
      $1,365,000
      5,489 SF

      119 Putnam Ave

      OFFICE BUILDING • 5,489 SF
      119 Putnam Ave, Cos Cob, CT 06807-2604
      View Details
    • Value Estimation
      $3,405,000
      7,897 SF

      99 Riv Rd

      OFFICE BUILDING • 7,897 SF
      99 Riv Rd, Cos Cob, CT 06807-2598
      View Details

    Similar Nearby for Sale

    • $1,575,000

      Buildable Lot with Existing Cottage

      0.52-acre lot with plans for a 4,200 sq. ft. home.
      9 Walnut St, Cos Cob, CT 06807
      View Details
    • $1,200,000

      Cos Cob Two-Family Home

      Two-family residence in Cos Cob with income-generating potential.
      67 Cos Cob Ave, Cos Cob, CT 06807
      View Details

    Similar Nearby for Lease

    • Contact for pricing
      5,054 SF

      Cos Cob Office Space Available

      5,054 SF office space with convenient access.
      31 River Rd, Cos Cob, CT 06807
      View Details
    • $7,500 /Mo

      Renovated Duplex Available for Rent

      Furnished, renovated 2-bedroom duplex available for short or long-term rental.
      84 E Putnam Ave, Cos Cob, CT 06807
      View Details
    • $4,000 /Mo

      Cos Cob Renovated Duplex

      Renovated 2-bedroom duplex in prime Cos Cob location.
      85 Strickland Rd, Cos Cob, CT 06807
      View Details
    • Contact for pricing

      Cos Cob Waterfront Condo Rental

      Updated 2-bedroom condo in waterfront community, convenient to train.
      9 River Road Ext, Cos Cob, CT 06807
      View Details
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    31 River Rd
    Cos Cob, CT 06807
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    Realmo Value Estimations

    Realmo estimates a property’s market value using a proprietary methodology that incorporates public data and user-submitted information. This cumulative value is generated by integrating a variety of conventional and innovative methods. 

    Disclaimer

    These figures are not official appraisals and should not be used as a substitute for a valuation performed by a licensed appraiser.
    Actual market value may differ due to factors not captured in the data. Estimates are offered for informational purposes only, and users should conduct independent research before making financial or investment decisions.
    By using this feature, you acknowledge that Realmo is not responsible for actions taken based on these estimates.

    AI approach

    Realmo AI Method estimates property value using machine learning models trained on millions of comparable listings, transactions, and market signals. It analyzes property features, location intelligence data, and current market dynamics to predict the most probable market value in real time.

    Realmo CapRate Calculation

    Realmo calculates the Capitalization Rate (Cap Rate) to help estimate a property's potential return on investment. The Cap Rate is a fundamental metric in commercial real estate that measures the relationship between a property's net operating income and its market value.

    How We Calculate Cap Rate

    Cap Rate Formula:
    Cap Rate (%) = (Net Operating Income / Property Value) × 100

    Net Operating Income (NOI) Formula:
    NOI = Area × Lease Rate × (1 - Vacancy Rate) × (1 - Operating Expense Ratio)

    Components

    Net Operating Income (NOI) represents the annual income a property generates after operating expenses:

    • Area: Building square footage from property records
    • Lease Rate: Annual $/sqft based on market data for the property type and geographic location
    • Vacancy Rate: Percentage of unoccupied space based on market data for the property type and location
    • Operating Expense Ratio: Operating costs as a percentage of income, varies by property type

    Property Value is derived from:

    • Recent sale price (if available)
    • Statistical models using comparable sales
    • AI-powered valuation estimates

    Example Calculation

    For a 100,000 sqft Office Building:

    • Lease Rate: $25.00/sqft/year (market data for Office in this area)
    • Vacancy Rate: 8% (market data for Office in this area)
    • Operating Expense Ratio: 35% (typical for Office properties)
    • Property Value: $15,000,000

    Step 1: Calculate NOI

    NOI = 100,000 × $25.00 × (1 - 0.08) × (1 - 0.35)
    NOI = 100,000 × $25.00 × 0.92 × 0.65
    NOI = $1,495,000/year

    Step 2: Calculate Cap Rate

    Cap Rate = ($1,495,000 / $15,000,000) × 100
    Cap Rate = 9.97%

    Property Type Considerations

    Net Operating Income calculations vary by property type due to different operating expense ratios:

    • Office: Higher expenses (30-40%) for HVAC, utilities, maintenance
    • Retail: Moderate expenses (25-35%) for common area maintenance
    • Industrial/Warehouse: Lower expenses (15-25%) for minimal tenant services
    • Multifamily: Moderate expenses (35-45%) including property management
    • Self-Storage: Lower expenses (25-35%) due to minimal maintenance

    Market lease rates and vacancy rates are specific to each property type and geographic location, reflecting local market conditions.

    Disclaimer

    These calculations are estimates for informational purposes only and should not be used as a substitute for professional financial analysis or appraisal.

    • Cap Rate calculations depend on market data that may change over time
    • Actual operating expenses, lease rates, and vacancy rates may differ from market averages
    • Individual property conditions, lease terms, and tenant quality significantly impact actual NOI
    • Property value estimates are approximations and not official appraisals
    • Cap rates vary widely by market, property condition, and investment risk profile

    Professional Guidance Recommended: Before making any investment or financial decisions, consult with licensed appraisers, commercial real estate brokers, and financial advisors who can evaluate your specific property and circumstances.
    By using this feature, you acknowledge that Realmo is not responsible for investment decisions or actions taken based on these estimates.

    Cap approach

    Capitalization Method calculates value based on estimated net operating income (NOI) and applying a market-based capitalization rate (cap rate), we estimate what a typical investor might be willing to pay for it.

    Comparable approach

    Comparable estimate is based on recent sales of similar nearby properties, adjusted for factors like size, condition, and location.

    Relative

    Relative property class coefficient uses factors that account for typical price differences between various asset types (e.g., retail vs. industrial) to provide a more accurate market-aligned estimate.

    Geo

    Comparable Sales Method, enhanced by Geo coefficients — location-based adjustment factors that reflect differences in price levels across neighborhoods, cities, or regions ensuring a more accurate, market-sensitive valuation.

    Stat Estimate

    This method estimates value based on actual market adjusted recent (~5 years) sales of comparable properties around by location and property type.

    • Ranges - area data calculated by industry standard IQR Outlier Removal Method
    • Range-from: 75% of all similar sales ($/sqft) are above this value
    • Range-to: 75% of all similar sales ($/sqft) are below this value
    AI Estimate

    This method estimates value based on AI market estimation of comparable properties around by location and property type.

    • Ranges - area data calculated by industry standard IQR Outlier Removal Method
    • Range-from: 75% of all estimations ($/sqft) are above this value
    • Range-to: 75% of all estimations ($/sqft) are below this value
    Alternative use

    Estimate considers the property’s potential value if used for a different purpose-based on zoning, demand, and market feasibility.

    More about this property
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