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Single Family ResidenceResidential
$1,145,761$593 / 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 92How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026
Last sold for $1,130,000 on Aug 25, 2025

423 RIVIERA DR

UNION CITY, CA 94587
5
Beds
2
Baths
1,932 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.
0.12 ac
Lot SizeThe size of the land the home sits on, from county records.
1967
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
9
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

$1.1M
$1M low$1.2M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$1,130,000 · Aug 25, 2025
Est. Owner EquityRoughly how much of the home's value the owner would keep after paying off known loans. It is our estimate minus the loans still owed.$241,761
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$193,409
Loan-to-ValueHow much is still owed on the home compared to what it is worth. 80% means loans equal 80% of our estimate, so it shifts when the estimate does.80%
1st MortgageA loan still believed to be open on this home, in the order lenders get repaid. The first position is paid back before the second.$904,000
BMO BANK NA · recorded Aug 25, 2025

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,198 (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.$1,130,000 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$339,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$791,000
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$337,690
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,083,420

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyALAMEDA
Lot (acres)The size of the land the home sits on, from county records.0.12
ConstructionThe main material the home's frame and walls are built from.Wood (Unspecified)
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(2)

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
Guy Emanuele Elementary SchoolB+
Elementary · Grades KG–5 · 1.0 mi
H
James Logan High SchoolA-
High · Grades 9–12 · 1.5 mi
M
Cesar Chavez Middle SchoolC-
Middle · Grades 6–8 · 2.7 mi

District: New Haven Unified School District

Neighborhood · ZIP 94587These 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.43
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.87
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.552

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.98%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.30%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.6.8%
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.66,162
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.5,241 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$129,537
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$155,780
Average tempThe average temperature here across a full year.58°F
Annual precipHow much rain and melted snow falls here in a typical year.19 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.78%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Absentee owner
Company ownedWhether the owner is a company or trust rather than a person.No

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

423 Riviera 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.

  • Costs less per square foot than 86% of homes in Union City 94587
  • Bigger than 73% of homes in Union City 94587
  • Has a smaller lot than 66% of homes in Union City 94587
  • Older than 87% of homes in Union City 94587

What homes are worth in Union City 94587

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

This home
$491K$2.2M

This home is worth more than 41% of homes in Union City 94587.

How it measures up in Union City 94587

The dot is this home. The mark in the middle is the typical home in Union City 94587.

Estimated value$1,145,761
CheaperTypical $1,249,625Pricier

Pricier than 41% of homes nearby

Price per ft²$593
CheaperTypical $733Pricier

Pricier than 14% of homes nearby

Living area1,932 ft²
SmallerTypical 1,563 ft²Bigger

Bigger than 73% of homes nearby

Lot size0.12 ac
SmallerTypical 0.14 acBigger

Bigger than 34% of homes nearby

Year built1967
OlderTypical 1977Newer

Newer than 13% of homes nearby

How 423 Riviera Dr ranks against every home in each area.
MeasureThis homeUnion City 94587Alameda County
Estimated valuepricier than$1,145,76141% of homes56% of homes
Price per ft²pricier than$59314% of homes36% of homes
Living areabigger than1,932 ft²73% of homes68% of homes
Lot sizebigger than0.12 ac34% of homes41% of homes
Year builtnewer than196713% of homes54% of homes

About 423 Riviera Dr

How much is 423 Riviera Dr, Union City, CA worth?

The TopHap Estimate for 423 Riviera Dr, Union City, CA is $1,145,761 as of Jul 14, 2026. The likely range is $1,049,661 to $1,241,861. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 423 Riviera Dr, Union City, CA last sell?

423 Riviera Dr, Union City, CA last sold on Aug 25, 2025 for $1,130,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 423 Riviera Dr, Union City, CA?

423 Riviera Dr, Union City, CA has 5 bedrooms, 2 bathrooms, 1,932 square feet of living space and a 0.12-acre lot.

When was 423 Riviera Dr, Union City, CA built?

423 Riviera Dr, Union City, CA was built in 1967, making it 59 years old. The building has 2 stories.

What schools serve 423 Riviera Dr, Union City, CA?

423 Riviera Dr, Union City, CA is assigned to Guy Emanuele Elementary School (elementary), rated B+; James Logan High School (high), rated A-; Cesar Chavez Middle School (middle), rated C-. All sit in New Haven Unified School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 423 Riviera Dr, Union City, CA compare to other homes in Union City 94587?

Among the 17,569 homes in Union City 94587, it is worth more than 41% of them ($1,145,761 against a typical $1,249,625), its price per square foot is higher than 14% of them ($593 against a typical $733), it is bigger than 73% of them (1,932 ft² against a typical 1,563 ft²), its lot is bigger than 34% of them (0.12 ac against a typical 0.14 ac) and it is newer than 13% of them (1967 against a typical 1977). Measured against all of Alameda County, it is worth more than 56% 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 423 Riviera Dr, Union City, CA?

The 2025 property tax bill for 423 Riviera Dr, Union City, CA was $5,198. The county assessed it at $1,130,000.

More homes on Riviera Dr

Closest homes

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Assigned schools

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