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Single Family ResidenceResidential
$807,937$656 / 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 95How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Oct 21, 2026
Last sold for $803,000 on Aug 25, 2026

3924 GRANDON AVE

SAN MARCOS, CA 92078
3
Beds
1.5
Baths
1,232 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.
0.16 ac
Lot SizeThe size of the land the home sits on, from county records.
1961
Year BuiltThe year the home was originally built, according to county records.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$808K
$770K low$846K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$803,000 · Aug 25, 2026

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$4,136 (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.$366,006 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$263,317
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$102,689
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$358,830

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.40
1
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
55
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
38
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
19
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
89
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.Single Family Residence
CountySAN DIEGO
Lot (acres)The size of the land the home sits on, from county records.0.16
GarageWhether the property has a garage, and details like whether it is attached to the home.Carport (Unspecified)
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(5)

Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.

Foreclosure Filings(3)

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

H
San Marcos High SchoolB
High · Grades 9–12 · 0.4 mi
E
La Mirada AcademyD+
Elementary · Grades KG–8 · 0.5 mi

District: San Marcos Unified School District

Neighborhood · ZIP 92078These 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.72
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.106
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.196

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.95%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.32%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.2%
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.49,873
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.$116,554
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$141,833
Average tempThe average temperature here across a full year.62°F
Annual precipHow much rain and melted snow falls here in a typical year.16 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.68%

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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

3924 Grandon Ave 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 less than 78% of homes in San Marcos 92078
  • Costs more per square foot than 84% of homes in San Marcos 92078
  • Smaller than 87% of homes in San Marcos 92078
  • Has a smaller lot than 84% of homes in Industrial San Marcos
  • Among the oldest homes in San Marcos 92078

What homes are worth in San Marcos 92078

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

This home
$503K$2.2M

This home is worth more than 22% of homes in San Marcos 92078.

How it measures up in San Marcos 92078

The dot is this home. The mark in the middle is the typical home in San Marcos 92078.

Estimated value$807,937
CheaperTypical $1,055,460Pricier

Pricier than 22% of homes nearby

Price per ft²$656
CheaperTypical $560Pricier

Pricier than 84% of homes nearby

Living area1,232 ft²
SmallerTypical 1,744 ft²Bigger

Bigger than 13% of homes nearby

Lot size0.16 ac
SmallerTypical 0.51 acBigger

Bigger than 24% of homes nearby

Year built1961
OlderTypical 2002Newer

Older than almost all homes nearby

How 3924 Grandon Ave ranks against every home in each area.
MeasureThis homeIndustrial San MarcosSan Marcos 92078San Diego County
Estimated valuepricier than$807,93769% of homes22% of homes42% of homes
Price per ft²pricier than$65677% of homes84% of homes68% of homes
Living areabigger than1,232 ft²38% of homes13% of homes33% of homes
Lot sizebigger than0.16 ac16% of homes24% of homes29% of homes
Year builtnewer than19615% of homesalmost no homes17% of homes

About 3924 Grandon Ave

How much is 3924 Grandon Ave, San Marcos, CA worth?

The TopHap Estimate for 3924 Grandon Ave, San Marcos, CA is $807,937 as of Oct 21, 2026. The likely range is $770,052 to $845,822. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 3924 Grandon Ave, San Marcos, CA last sell?

3924 Grandon Ave, San Marcos, CA last sold on Aug 25, 2026 for $803,000, according to the county's recorded deed. TopHap holds 4 recorded sales for this parcel.

How big is 3924 Grandon Ave, San Marcos, CA?

3924 Grandon Ave, San Marcos, CA has 3 bedrooms, 1.5 bathrooms, 1,232 square feet of living space and a 0.16-acre lot.

When was 3924 Grandon Ave, San Marcos, CA built?

3924 Grandon Ave, San Marcos, CA was built in 1961, making it 65 years old.

What schools serve 3924 Grandon Ave, San Marcos, CA?

3924 Grandon Ave, San Marcos, CA is assigned to San Marcos High School (high), rated B; La Mirada Academy (elementary), rated D+. All sit in San Marcos Unified School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 3924 Grandon Ave, San Marcos, CA compare to other homes in San Marcos 92078?

Among the 16,678 homes in San Marcos 92078, it is worth more than 22% of them ($807,937 against a typical $1,055,460), its price per square foot is higher than 84% of them ($656 against a typical $560), it is bigger than 13% of them (1,232 ft² against a typical 1,744 ft²), its lot is bigger than 24% of them (0.16 ac against a typical 0.51 ac) and it is newer than almost none of them (1961 against a typical 2002). Measured against all of San Diego County, it is worth more than 42% 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 3924 Grandon Ave, San Marcos, CA?

The 2025 property tax bill for 3924 Grandon Ave, San Marcos, CA was $4,136. The county assessed it at $366,006.

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