Skip to content
Skip to content
TopHapOpen in map
Single Family ResidenceResidential
$372,544$229 / ft²
TopHap EstimateOur estimate of what this home would sell for today, based on nearby sales, the home's size and features, and local price trends. It is a starting point, not an appraisal.· confidence 83How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Aug 30, 2026
Last sold for $94,000 on May 17, 2006

509 12TH ST

ALTON, IA 51003
2
Baths
1,624 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.
0.19 ac
Lot SizeThe size of the land the home sits on, from county records.
2012
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
5
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$373K
$310K low$435K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$94,000 · May 17, 2006

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$4,718 (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.$333,520 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$18,330
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$315,190
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$268,280
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$333,520

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountySIOUX
Lot (acres)The size of the land the home sits on, from county records.0.19
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
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Attached
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 · 112 ft²

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.

M
Moc-Floyd Valley Middle SchoolB
Middle · Grades 6–8 · 0.1 mi
E
Moc-Floyd Valley Elementary SchoolB+
Elementary · Grades PK–5 · 1.1 mi
H
Moc-Floyd Valley High SchoolA-
High · Grades 9–12 · 2.0 mi

District: Moc-Floyd Valley Community School District

Neighborhood · ZIP 51003These 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.117
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.84
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.18

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.17%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.4.2%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.8%
PopulationHow many people live in this area.2,164
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.39 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$88,017
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$109,952
Average tempThe average temperature here across a full year.46°F
Annual precipHow much rain and melted snow falls here in a typical year.28 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.61%

Owner Tools

Do you own this home?
Claim this home

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

509 12th 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.

  • Worth more than 74% of homes in Alton 51003
  • Costs more per square foot than 78% of homes in Alton 51003
  • Has a smaller lot than 85% of homes in Alton 51003
  • Newer than 89% of homes in Sioux County

What homes are worth in Alton 51003

Each bar is how many homes fall in that price range. The marker is this home.

This home
$96K$710K

This home is worth more than 74% of homes in Alton 51003.

How it measures up in Alton 51003

The dot is this home. The mark in the middle is the typical home in Alton 51003.

Estimated value$372,544
CheaperTypical $261,080Pricier

Pricier than 74% of homes nearby

Price per ft²$229
CheaperTypical $172Pricier

Pricier than 78% of homes nearby

Living area1,624 ft²
SmallerTypical 1,632 ft²Bigger

Bigger than 50% of homes nearby

Lot size0.19 ac
SmallerTypical 0.4 acBigger

Bigger than 15% of homes nearby

Year built2012
OlderTypical 1958Newer

Newer than 88% of homes nearby

How 509 12th St ranks against every home in each area.
MeasureThis homeAlton 51003Sioux County
Estimated valuepricier than$372,54474% of homes72% of homes
Price per ft²pricier than$22978% of homes67% of homes
Living areabigger than1,624 ft²50% of homes60% of homes
Lot sizebigger than0.19 ac15% of homes16% of homes
Year builtnewer than201288% of homes89% of homes

About 509 12th St

How much is 509 12th St, Alton, IA worth?

The TopHap Estimate for 509 12th St, Alton, IA is $372,544 as of Aug 30, 2026. The likely range is $310,235 to $434,853. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 509 12th St, Alton, IA last sell?

509 12th St, Alton, IA last sold on May 17, 2006 for $94,000, according to the county's recorded deed.

How big is 509 12th St, Alton, IA?

509 12th St, Alton, IA has 2 bathrooms, 1,624 square feet of living space and a 0.19-acre lot.

When was 509 12th St, Alton, IA built?

509 12th St, Alton, IA was built in 2012, making it 14 years old. The building has 1 story.

What schools serve 509 12th St, Alton, IA?

509 12th St, Alton, IA is assigned to Moc-Floyd Valley Middle School (middle), rated B; Moc-Floyd Valley Elementary School (elementary), rated B+; Moc-Floyd Valley High School (high), rated A-. All sit in Moc-Floyd Valley Community School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 509 12th St, Alton, IA compare to other homes in Alton 51003?

Among the 670 homes in Alton 51003, it is worth more than 74% of them ($372,544 against a typical $261,080), its price per square foot is higher than 78% of them ($229 against a typical $172), it is bigger than 50% of them (1,624 ft² against a typical 1,632 ft²), its lot is bigger than 15% of them (0.19 ac against a typical 0.4 ac) and it is newer than 88% of them (2012 against a typical 1958). Measured against all of Sioux County, it is worth more than 72% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 509 12th St, Alton, IA?

The 2025 property tax bill for 509 12th St, Alton, IA was $4,718. The county assessed it at $333,520.

More homes on 12th St

Closest homes

More homes in Alton 51003

Assigned schools

Explore the area

See this home in context

Open 509 12th St on TopHap’s interactive map to compare it against every sale nearby, overlay school zones and flood risk, and run a CMA.

Open in map
A flyover of TopHap's photorealistic 3D map, with recorded sale prices pinned to homes
Search any address, city, zip, or county…3D$1.9M$6.25MOpen in map