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CondominiumResidential

23 Union St

CHARLESTOWN, MA 02129
606 ft²
Lot SizeThe size of the land the home sits on, from county records.
1870
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
1
ParkingThe number of parking spaces on the property, including the garage.
Built 18704 units606–775 ft²
$2.6M
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.
$659K
Median unit valueThe middle unit value in this building by our estimate: half the units are worth more, half less.
$999
Median $/ft²The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.

+21.7%vs the Charlestown ZIP median sale $/ft² ($821)

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.
+7.9%per yeartypical hold 8.5 yrsfrom 6 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
19911995199819992000200620172021
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
19911995199819992000200620172021

10 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.

1 bed
1 unit
2 bed
3 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.

$571K–$571K
1 unit
$609K–$609K
1 unit
$709K–$728K
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.25%
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.14.6 yrs
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.53%
Median owner equityThe middle dollar amount of equity (value minus loans) unit owners hold in this building.$753,714
Median tax billThe middle annual property tax bill among the building's units.$6,441
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 4Aug 9, 2021$725,000Unit 3Jun 27, 2017$570,000Unit 1Dec 1, 2006$299,999Unit 4May 17, 2000$277,000Unit 2May 24, 1999$195,000Unit 1Jun 16, 1998$147,000Unit 2Mar 30, 1995$125,000Unit 4Nov 5, 1991$131,000Unit 3Nov 4, 1991$100,000Unit 1May 6, 1991$135,000

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

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Condominium
CountySUFFOLK
Lot (acres)The size of the land the home sits on, from county records.0.01
HeatingThe type of heating system in the home.Hot Water
PoolWhether the property has a pool, and what kind, such as in-ground.No
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Deck

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

E
Warren / Prescott K-8 SchoolA-
Elementary · Grades PK–8 · 0.3 mi
H
Horace Mann School For The Deaf
High · Grades PK–12 · 0.4 mi

District: Boston School District

Neighborhood · ZIP 02129These 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.89
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.101
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.73

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.35%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.8.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.3%
PopulationHow many people live in this area.18,397
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.10,594 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$152,177
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$178,903
Average tempThe average temperature here across a full year.50°F
Annual precipHow much rain and melted snow falls here in a typical year.46 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.

23 Union St # 1
2 bd · 1 ba · 775 ft²
$571K
23 Union St
1 bd · 1 ba · 606 ft²
$609K
23 Union St
2 bd · 1 ba · 699 ft²
$728K
23 Union St # 4
2 bd · 1 ba · 714 ft²
$709K

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

About 23 Union St

How many units are in 23 Union St, Charlestown, MA?

23 Union St, Charlestown, MA has 4 residential units across built in 1870, according to county assessor records.

What is a unit at 23 Union St, Charlestown, MA worth?

The median TopHap Estimate across the 4 units at 23 Union St, Charlestown, MA is $659,333. That works out to $999 per square foot. Units run from 606 to 775 square feet. Estimates are modelled from recorded sales and assessments, not appraisals.

Is 23 Union St, Charlestown, MA expensive for Charlestown?

Units at 23 Union St, Charlestown, MA carry a median of $999 per square foot, 22% above the Charlestown median of $821 per square foot.

How often do units sell at 23 Union St, Charlestown, MA?

0 units at 23 Union St, Charlestown, MA sold in the last 12 months, out of 10 recorded arms-length sales all time. That is a turnover rate of 0.0% of the building per year.

Have units at 23 Union St, Charlestown, MA appreciated?

Across 6 repeat sales of the same unit, 23 Union St, Charlestown, MA returned a median 7.9% 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 8.5 years.

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