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Mobile HomeResidential

421 SWANZEY ST

KEYSTONE, SD 57751
0
Baths
3,136 ft²
Living AreaTotal finished area of the structures, from county records. Some counties include shared space like hallways or a building gym, so it may not match a listing.
0.79 ac
Lot SizeThe size of the land the home sits on, from county records.
1996
Year BuiltThe year the home was originally built, according to county records.

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$1,809 (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.$257,500 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$78,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$179,500
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$180,000

Climate Risk

Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.197 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.51%
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.Mobile Home
StyleThe architectural style of the home, such as ranch or colonial.Mobile/Manufactured
CountyPENNINGTON
Lot (acres)The size of the land the home sits on, from county records.0.79
PoolWhether the property has a pool, and what kind, such as in-ground.No

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

M
Hill City Middle School - 04B
Middle · Grades 6–8 · 8.2 mi
H
Hill City High School - 01A
High · Grades 9–12 · 8.3 mi
E
Hill City Elementary - 02A-
Elementary · Grades PK–5 · 8.3 mi

District: Hill City School District 51-2

Neighborhood · ZIP 57751These 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.109
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.104
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.39

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.78%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.25%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.3.6%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.6%
PopulationHow many people live in this area.794
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.12 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$111,312
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$130,793
Average tempThe average temperature here across a full year.46°F
Annual precipHow much rain and melted snow falls here in a typical year.20 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.63%

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

How this home compares

421 Swanzey St measured against every home in its neighborhood, its ZIP code and its county, using county assessor records refreshed nightly. A home can stand out in one of those areas and look ordinary in another, because each one holds a different mix of homes.

  • Bigger than 87% of homes in Keystone 57751
  • Has a bigger lot than 77% of homes in Pennington County
  • Newer than 66% of homes in Pennington County

How it measures up in Keystone 57751

The dot is this home. The mark in the middle is the typical home in Keystone 57751.

Living area3,136 ft²
SmallerTypical 1,600 ft²Bigger

Bigger than 87% of homes nearby

Lot size0.79 ac
SmallerTypical 3.18 acBigger

Bigger than 24% of homes nearby

Year built1996
OlderTypical 1996Newer

Newer than 51% of homes nearby

How 421 Swanzey St ranks against every home in each area.
MeasureThis homeKeystone 57751Pennington County
Living areabigger than3,136 ft²87% of homes87% of homes
Lot sizebigger than0.79 ac24% of homes77% of homes
Year builtnewer than199651% of homes66% of homes

About 421 Swanzey St

When did 421 Swanzey St, Keystone, SD last sell?

421 Swanzey St, Keystone, SD last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 421 Swanzey St, Keystone, SD?

421 Swanzey St, Keystone, SD has 3,136 square feet of living space and a 0.79-acre lot.

When was 421 Swanzey St, Keystone, SD built?

421 Swanzey St, Keystone, SD was built in 1996, making it 30 years old. It is a mobile/manufactured home.

What schools serve 421 Swanzey St, Keystone, SD?

421 Swanzey St, Keystone, SD is assigned to Hill City Middle School - 04 (middle), rated B; Hill City High School - 01 (high), rated A; Hill City Elementary - 02 (elementary), rated A-. All sit in Hill City School District 51-2. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 421 Swanzey St, Keystone, SD compare to other homes in Keystone 57751?

Among the 448 homes in Keystone 57751, it is bigger than 87% of them (3,136 ft² against a typical 1,600 ft²), its lot is bigger than 24% of them (0.79 ac against a typical 3.18 ac) and it is newer than 51% of them (1996 against a typical 1996). These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 421 Swanzey St, Keystone, SD?

The 2025 property tax bill for 421 Swanzey St, Keystone, SD was $1,809. The county assessed it at $257,500.

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