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CondominiumResidential
Last sold for $145,000 on Apr 14, 2026

12643 S KOSTNER AVE

ALSIP, IL 60803
0.66 ac
Lot SizeThe size of the land the home sits on, from county records.
1973
Year BuiltThe year the home was originally built, according to county records.
Built 19735 units741–1,102 ft²
$643K
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.
$130K
Median unit valueThe middle unit value in this building by our estimate: half the units are worth more, half less.
$137
Median $/ft²The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.

-41.2%vs the Alsip ZIP median sale $/ft² ($233)

Sales Performance

$145K
Median sale (12 mo)The middle sale price among this building's units that sold in the last 12 months, from recorded deeds.
—
1-yr changeHow the building's median sale price over the last 12 months compares with the 12 months before that.
1
Sales (12 mo)Units in this building that sold in the last 12 months, from recorded arms-length deeds.
20.0%
Turnover (12 mo)The share of units that changed hands in the last 12 months. Around 4–6% a year is typical; much higher can signal investor churn or a wave of exits.
Median sale price (yearly, all time)Every recorded arms-length sale in the building since records begin, grouped by year: the bars count sales and the line tracks the median price paid.MedianSales
19992002201420192020202220242026
Sale price per ft² (yearly, all time)The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.$/ft²
19992002201420192020202220242026

9 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
4 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.
2 bd · 1 ba · 1,057 ft²
2 units
One-off layouts
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.

$103K–$103K
1 unit
$129K–$130K
2 units
$137K–$137K
1 unit
$145K–$145K
1 unit

Ownership & Financing

Owner-occupiedThe share of units where the owner lives in the unit, per county records. The rest are second homes or rentals.80%
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.5.7 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.0%
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.55%
Median owner equityThe middle dollar amount of equity (value minus loans) unit owners hold in this building.$122,529
Median tax billThe middle annual property tax bill among the building's units.$1,878
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.

BuildingApr 14, 2026$145,000Unit 2BJun 25, 2024$130,000Unit 2ADec 2, 2022$106,000Unit 2BJul 30, 2020$60,000Unit 1BJan 3, 2019$43,000Unit 1BOct 14, 2014$37,500Unit 2ASep 17, 2014$45,000Unit 3AJan 14, 2002$62,500BuildingOct 26, 1999$65,000

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

Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$9,208 (2024)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$901
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$8,307
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$9,207
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$92,080

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.39
1
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
7
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
72
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
75
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
40
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.

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
CountyCook
Lot (acres)The size of the land the home sits on, from county records.0.66
HeatingThe type of heating system in the home.None

Transaction History(4)

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
Lane Elementary SchoolB
Elementary · Grades KG–6 · 0.6 mi
M
Prairie Junior High SchoolA-
Middle · Grades 7–8 · 0.9 mi
H
Alan B. Shepard High SchoolC-
High · Grades 9–12 · 2.5 mi

District: Alsip-Hazelgreen-Oaklawn School District 126

Neighborhood · ZIP 60803These 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.97
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.108
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.46

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.96%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.13%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.11%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.6%
PopulationHow many people live in this area.20,810
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.2,847 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$68,007
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$86,389
Average tempThe average temperature here across a full year.50°F
Annual precipHow much rain and melted snow falls here in a typical year.38 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.54%

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.

12643 S Kostner Ave
2 bd · 1 ba · 1,102 ft²
$150K
12643 S Kostner Ave Apt 1b
1 bd · 1 ba · 741 ft²
$103K
12643 S Kostner Ave # 2a
2 bd · 1 ba · 900 ft²
$129K
12643 S Kostner Ave Apt 2b
2 bd · 1 ba · 1,057 ft²
$145K
12643 S Kostner Ave Apt 3a
2 bd · 1 ba · 1,057 ft²
$130K
12643 S Kostner Ave Apt 3b
2 bd · 1 ba · 1,102 ft²
$137K

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

About 12643 S Kostner Ave

How many units are in 12643 S Kostner Ave, Alsip, IL?

12643 S Kostner Ave, Alsip, IL has 5 residential units across built in 1973, according to county assessor records.

What is a unit at 12643 S Kostner Ave, Alsip, IL worth?

The median TopHap Estimate across the 5 units at 12643 S Kostner Ave, Alsip, IL is $129,718. That works out to $137 per square foot. Units run from 741 to 1,102 square feet. Estimates are modelled from recorded sales and assessments, not appraisals.

Is 12643 S Kostner Ave, Alsip, IL expensive for Alsip?

Units at 12643 S Kostner Ave, Alsip, IL carry a median of $137 per square foot, 41% below the Alsip median of $233 per square foot.

How often do units sell at 12643 S Kostner Ave, Alsip, IL?

1 units at 12643 S Kostner Ave, Alsip, IL sold in the last 12 months, out of 9 recorded arms-length sales all time. That is a turnover rate of 20.0% of the building per year. The median sale over that period was $145K.

Have units at 12643 S Kostner Ave, Alsip, IL appreciated?

Across 4 repeat sales of the same unit, 12643 S Kostner Ave, Alsip, IL returned a median 7.1% 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 6.2 years.

What floor plans does 12643 S Kostner Ave, Alsip, IL have?

The most common plan at 12643 S Kostner Ave, Alsip, IL is a 2-bedroom of 1,057 square feet, repeated 2 times, with a median estimate of $137,237. TopHap identifies 1 recurring plans in the building.

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