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Single Family ResidenceResidential
$640,167$325 / 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 93How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Sep 24, 2026

21C GRINDSTONE DR

PROSPER, TX 75078
4
Beds
2
Baths
1,968 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.
1.05 ac
Lot SizeThe size of the land the home sits on, from county records.
1994
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
7
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

$640K
$597K low$684K high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$8,721 (2024)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$553,000 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$209,100
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$343,900
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$563,323
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$553,000

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyCollin
Effective Year BuiltAn adjusted build year that accounts for condition and major remodels. A big renovation can make a home count as newer than it is.2005
Lot (acres)The size of the land the home sits on, from county records.1.05
ConstructionThe main material the home's frame and walls are built from.Frame (Unspecified)
FoundationWhat the home is built on, such as a concrete slab, a crawl space, or a basement.Mat/Raft Foundation (Slab)
RoofThe main material covering the roof, such as asphalt shingle or tile.Composition Shingle
HeatingThe type of heating system in the home.Central
CoolingThe type of cooling or air conditioning in the home.Central
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, Attached
PoolWhether the property has a pool, and what kind, such as in-ground.Yes
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 166 ft²

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

E
Cynthia A. Cockrell Elementary SchoolA+
Elementary · Grades KG–5 · 0.4 mi
H
Walnut Grove High School
High · Grades 9–12 · 1.6 mi
M
Rogers Middle SchoolA+
Middle · Grades 6–8 · 2.7 mi

District: Prosper Independent School District

Neighborhood · ZIP 75078These 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.49
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 100.29

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.41%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.3.2%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.4%
PopulationHow many people live in this area.49,045
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.1,435 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$166,233
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$200,017
Average tempThe average temperature here across a full year.64°F
Annual precipHow much rain and melted snow falls here in a typical year.40 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.62%

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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

21c Grindstone Dr 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 71% of homes in Collin County
  • Costs more per square foot than 97% of homes in Collin County
  • Smaller than 94% of homes in Prosper 75078
  • Has a bigger lot than 95% of homes in Prosper 75078
  • Older than 97% of homes in Prosper 75078

What homes are worth in Prosper 75078

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

This home
$366K$1.8M

This home is worth more than 31% of homes in Prosper 75078.

How it measures up in Prosper 75078

The dot is this home. The mark in the middle is the typical home in Prosper 75078.

Estimated value$640,167
CheaperTypical $747,798Pricier

Pricier than 31% of homes nearby

Price per ft²$325
CheaperTypical $224Pricier

Pricier than 95% of homes nearby

Living area1,968 ft²
SmallerTypical 3,428 ft²Bigger

Bigger than 6% of homes nearby

Lot size1.05 ac
SmallerTypical 0.21 acBigger

Bigger than 95% of homes nearby

Year built1994
OlderTypical 2018Newer

Newer than 3% of homes nearby

How 21c Grindstone Dr ranks against every home in each area.
MeasureThis homeProsper 75078Collin County
Estimated valuepricier than$640,16731% of homes71% of homes
Price per ft²pricier than$32595% of homes97% of homes
Living areabigger than1,968 ft²6% of homes29% of homes
Lot sizebigger than1.05 ac95% of homes89% of homes
Year builtnewer than19943% of homes27% of homes

About 21c Grindstone Dr

How much is 21c Grindstone Dr, Prosper, TX worth?

The TopHap Estimate for 21c Grindstone Dr, Prosper, TX is $640,167 as of Sep 24, 2026. The likely range is $596,755 to $683,579. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 21c Grindstone Dr, Prosper, TX last sell?

21c Grindstone Dr, Prosper, TX last sold on Apr 17, 1995, according to the county's recorded deed.

How big is 21c Grindstone Dr, Prosper, TX?

21c Grindstone Dr, Prosper, TX has 4 bedrooms, 2 bathrooms, 1,968 square feet of living space and a 1.05-acre lot.

When was 21c Grindstone Dr, Prosper, TX built?

21c Grindstone Dr, Prosper, TX was built in 1994, making it 32 years old. The building has 1 story.

What schools serve 21c Grindstone Dr, Prosper, TX?

21c Grindstone Dr, Prosper, TX is assigned to Cynthia A. Cockrell Elementary School (elementary), rated A+; Walnut Grove High School (high); Rogers Middle School (middle), rated A+. All sit in Prosper Independent School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21c Grindstone Dr, Prosper, TX compare to other homes in Prosper 75078?

Among the 19,498 homes in Prosper 75078, it is worth more than 31% of them ($640,167 against a typical $747,798), its price per square foot is higher than 95% of them ($325 against a typical $224), it is bigger than 6% of them (1,968 ft² against a typical 3,428 ft²), its lot is bigger than 95% of them (1.05 ac against a typical 0.21 ac) and it is newer than 3% of them (1994 against a typical 2018). Measured against all of Collin County, it is worth more than 71% 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 21c Grindstone Dr, Prosper, TX?

The 2024 property tax bill for 21c Grindstone Dr, Prosper, TX was $8,721. The county assessed it at $553,000.

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