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CondominiumResidential
Last sold for $660,000 on Nov 30, 2018

6 ROBERTSON LN

COS COB, CT 06807
1998
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
1
ParkingThe number of parking spaces on the property, including the garage.
Built 19984 units1,468–2,094 ft²
$4.6M
All units combinedThe sum of our current value estimates for every unit in the building — roughly what the whole building's homes are worth together.
$1.2M
Median unit valueThe middle unit value in this building by our estimate: half the units are worth more, half less.
$596
Median $/ft²The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.

-13.7%vs the Cos Cob ZIP median sale $/ft² ($690)

Sales Performance

—
Median sale (12 mo)The middle sale price among this building's units that sold in the last 12 months, from recorded deeds.
—
1-yr changeHow the building's median sale price over the last 12 months compares with the 12 months before that.
0
Sales (12 mo)Units in this building that sold in the last 12 months, from recorded arms-length deeds.
0.0%
Turnover (12 mo)The share of units that changed hands in the last 12 months. Around 4–6% a year is typical; much higher can signal investor churn or a wave of exits.
This building's own appreciationThe building's own appreciation: for every unit that sold twice (held over a year), we compute its yearly price change between the two sales and take the middle value. This is the cleanest read on how this specific building performs, because it compares each unit to itself.
+3.3%per yeartypical hold 11.7 yrsfrom 5 same-unit resales
Median sale price (yearly, all time)Every recorded arms-length sale in the building since records begin, grouped by year: the bars count sales and the line tracks the median price paid.MedianSales
19981999200220042014201820232025
Sale price per ft² (yearly, all time)The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.$/ft²
19981999200220042014201820232025

11 arms-length sales on record for this building.

Unit Mix & Floor PlansThe building's recurring floor plans, found by grouping units with identical beds, baths and square footage in county records. Larger groups are the building's standard layouts; leftover units have one-off sizes.

2 bed
1 unit
3 bed
3 units
Recurring floor plansThe building's recurring floor plans, found by grouping units with identical beds, baths and square footage in county records. Larger groups are the building's standard layouts; leftover units have one-off sizes.
3 bd · 2.5 ba · 2,094 ft²
2 units
One-off layouts
2 units

Value DistributionHow the building's units spread across value ranges by our current estimates. A wide spread usually means big differences in size, floor or view.

$975K–$975K
1 unit
$1.2M–$1.2M
1 unit
$1.2M–$1.2M
2 units

Ownership & Financing

Owner-occupiedThe share of units where the owner lives in the unit, per county records. The rest are second homes or rentals.100%
Company-ownedUnits owned through an LLC, trust, or other company — a rough proxy for investor ownership.0%
Typical owner tenureThe middle number of years since each unit last changed hands — how long the current owners have been in place.3.9 yrs
Cash purchases (5 yrs)The share of purchases in the last 5 years with no mortgage recorded. High cash share is common in second-home and investor buildings.33%
Avg. loan-to-valueAverage current loan balance against unit value across the building. Low numbers mean owners hold lots of equity — a sign of financial stability.39%
Median owner equityThe middle dollar amount of equity (value minus loans) unit owners hold in this building.$1,220,231
Median tax billThe middle annual property tax bill among the building's units.$6,646
Pre-foreclosure noticesUnits with an active pre-foreclosure or foreclosure notice on file.0

Recent SalesThe latest recorded arms-length sales in the building, newest first.

Unit 7Apr 28, 2025$925,000Unit 4Jan 30, 2023$905,000Unit 5May 10, 2022$940,000BuildingNov 30, 2018$660,000Unit 3Feb 26, 2014$722,000Unit 5Dec 27, 2004$810,000Unit 3Jul 3, 2002$575,000Unit 5Mar 29, 2001$569,000Unit 4Mar 9, 1999$420,000Unit 5Jul 8, 1998$380,000

Values are TopHap estimates, not appraisals. Sales, ownership and tax figures come from recorded county documents via ATTOM and can lag by several weeks.

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,596 (2025)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$452,760 (2025)
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$452,760
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$452,760
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$316,932

Climate Risk

Overall riskThe average of the five hazard scores below, on a 0 to 100 scale. Higher means greater projected risk over the coming decades.55
67
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
5
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
64
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
96
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
43
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.
Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.72 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.62%
FEMA Flood ZoneFEMA's flood zone for this address. Zones starting with A or V are high risk, and lenders usually require flood insurance there.1 percent flood zone

Scores 0–100; higher = greater projected risk.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Condominium
StyleThe architectural style of the home, such as ranch or colonial.Condo/Apartment
CountyWESTERN CONNECTICUT
ConstructionThe main material the home's frame and walls are built from.Frame (Unspecified)
RoofThe main material covering the roof, such as asphalt shingle or tile.Asphalt
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
CoolingThe type of cooling or air conditioning in the home.Yes
FireplaceWhether the home has a fireplace, and what kind.Yes
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Basement
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(1)

Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.

Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.

E
Cos Cob SchoolB
Elementary · Grades KG–5 · 0.1 mi
M
Central Middle SchoolA-
Middle · Grades 6–8 · 0.8 mi
H
Greenwich High SchoolA+
High · Grades 9–12 · 0.9 mi

District: Greenwich School District

Neighborhood · ZIP 06807These are comparison scores, not percentages. 100 equals the national average, so 150 means about 50% above average.

CrimeLocal crime compared with the rest of the country, where 100 is average. It reflects things like population density, income, and how crime gets reported.54
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.112
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.103

Index scale: 100 = US average (tick). Lower is better.

Homes occupiedThe share of homes here that someone lives in. The rest sit empty, including vacation and for-sale homes.94%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.34%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.6.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.0%
PopulationHow many people live in this area.7,630
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.2,321 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$180,144
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$235,340
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.51 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.58%

All UnitsEvery property record the county has at this street address, such as the units in a condo building. Prices shown are our estimates, not asking prices.

6 Robertson Ln
2 bd · 2.5 ba · 1,469 ft²
$957K
6 Robertson Ln # 3
3 bd · 2.5 ba · 1,982 ft²
$1.2M
6 Robertson Ln # 4
3 bd · 2.5 ba · 2,094 ft²
$1.2M
6 Robertson Ln # 5
3 bd · 2.5 ba · 2,094 ft²
$1.2M
6 Robertson Ln # 7
2 bd · 3 ba · 1,468 ft²
$975K

Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.

About 6 Robertson Ln

How many units are in 6 Robertson Ln, Cos Cob, CT?

6 Robertson Ln, Cos Cob, CT has 4 residential units across built in 1998, according to county assessor records.

What is a unit at 6 Robertson Ln, Cos Cob, CT worth?

The median TopHap Estimate across the 4 units at 6 Robertson Ln, Cos Cob, CT is $1,192,947. That works out to $596 per square foot. Units run from 1,468 to 2,094 square feet. Estimates are modelled from recorded sales and assessments, not appraisals.

Is 6 Robertson Ln, Cos Cob, CT expensive for Cos Cob?

Units at 6 Robertson Ln, Cos Cob, CT carry a median of $596 per square foot, 14% below the Cos Cob median of $690 per square foot.

How often do units sell at 6 Robertson Ln, Cos Cob, CT?

0 units at 6 Robertson Ln, Cos Cob, CT sold in the last 12 months, out of 11 recorded arms-length sales all time. That is a turnover rate of 0.0% of the building per year.

Have units at 6 Robertson Ln, Cos Cob, CT appreciated?

Across 5 repeat sales of the same unit, 6 Robertson Ln, Cos Cob, CT returned a median 3.3% per year. Because each pair is the same unit bought and sold, the figure is not distorted by which units traded. The median owner held for 11.7 years.

What floor plans does 6 Robertson Ln, Cos Cob, CT have?

The most common plan at 6 Robertson Ln, Cos Cob, CT is a 3-bedroom of 2,094 square feet, repeated 2 times, with a median estimate of $1,200,644. TopHap identifies 1 recurring plans in the building.

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Assigned schools

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