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Single Family ResidenceResidential

13 LOWER ALCATRAZ PL

MILL VALLEY, CA 94941
2,000 ft²
Lot SizeThe size of the land the home sits on, from county records.
1908
Year BuiltThe year the home was originally built, according to county records.
Built 19202 units541–1,051 ft²
$2.5M
All units combinedThe sum of our current value estimates for every unit in the building — roughly what the whole building's homes are worth together.
$1.2M
Median unit valueThe middle unit value in this building by our estimate: half the units are worth more, half less.
$1632
Median $/ft²The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.

+36.9%vs the Mill Valley ZIP median sale $/ft² ($1192)

Sales Performance

—
Median sale (12 mo)The middle sale price among this building's units that sold in the last 12 months, from recorded deeds.
—
1-yr changeHow the building's median sale price over the last 12 months compares with the 12 months before that.
0
Sales (12 mo)Units in this building that sold in the last 12 months, from recorded arms-length deeds.
0.0%
Turnover (12 mo)The share of units that changed hands in the last 12 months. Around 4–6% a year is typical; much higher can signal investor churn or a wave of exits.
Median sale price (yearly, all time)Every recorded arms-length sale in the building since records begin, grouped by year: the bars count sales and the line tracks the median price paid.MedianSales
20012002200720142021
Sale price per ft² (yearly, all time)The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.$/ft²
20012002200720142021

5 arms-length sales on record for this building.

Unit Mix & Floor PlansThe building's recurring floor plans, found by grouping units with identical beds, baths and square footage in county records. Larger groups are the building's standard layouts; leftover units have one-off sizes.

2 bed
2 units

Ownership & Financing

Owner-occupiedThe share of units where the owner lives in the unit, per county records. The rest are second homes or rentals.50%
Company-ownedUnits owned through an LLC, trust, or other company — a rough proxy for investor ownership.50%
Typical owner tenureThe middle number of years since each unit last changed hands — how long the current owners have been in place.12.3 yrs
Avg. loan-to-valueAverage current loan balance against unit value across the building. Low numbers mean owners hold lots of equity — a sign of financial stability.76%
Median owner equityThe middle dollar amount of equity (value minus loans) unit owners hold in this building.$1,079,296
Median tax billThe middle annual property tax bill among the building's units.$16,265
Pre-foreclosure noticesUnits with an active pre-foreclosure or foreclosure notice on file.0

Recent SalesThe latest recorded arms-length sales in the building, newest first.

Unit CJun 4, 2021$1,200,000Unit COct 24, 2014$750,000Unit BAug 24, 2007$695,000Unit BMay 3, 2002$293,500BuildingSep 10, 2001$201,000

Values are TopHap estimates, not appraisals. Sales, ownership and tax figures come from recorded county documents via ATTOM and can lag by several weeks.

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$4,116 (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.$51,876 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$21,881
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$29,995
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$50,859

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
StyleThe architectural style of the home, such as ranch or colonial.Contemporary
CountyMARIN
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.1920
Lot (acres)The size of the land the home sits on, from county records.0.05
FireplaceWhether the home has a fireplace, and what kind.Yes
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 · 138 ft²Patio · 138 ft²

Transaction History(3)

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
Old Mill Elementary SchoolA+
Elementary · Grades KG–5 · 0.3 mi
M
Mill Valley Middle SchoolA+
Middle · Grades 6–8 · 1.4 mi
H
Tamalpais High SchoolA
High · Grades 9–12 · 1.6 mi

District: Mill Valley Elementary School District

Neighborhood · ZIP 94941These 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.91
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 100.439

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.93%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.37%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.5.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.1%
PopulationHow many people live in this area.30,767
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.1,462 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$194,124
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$248,795
Average tempThe average temperature here across a full year.57°F
Annual precipHow much rain and melted snow falls here in a typical year.42 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.78%

All UnitsEvery property record the county has at this street address, such as the units in a condo building. Prices shown are our estimates, not asking prices.

13 Lower Alcatraz Pl
2 bd · 1.5 ba · 702 ft²
13 Lower Alcatraz Pl # B
2 bd · 1 ba · 541 ft²
$1M
13 Lower Alcatraz Pl
2 bd · 2 ba · 1,051 ft²
$1.5M

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

About 13 Lower Alcatraz Pl

How many units are in 13 Lower Alcatraz Pl, Mill Valley, CA?

13 Lower Alcatraz Pl, Mill Valley, CA has 2 residential units across built in 1920, according to county assessor records.

What is a unit at 13 Lower Alcatraz Pl, Mill Valley, CA worth?

The median TopHap Estimate across the 2 units at 13 Lower Alcatraz Pl, Mill Valley, CA is $1,243,161. That works out to $1632 per square foot. Units run from 541 to 1,051 square feet. Estimates are modelled from recorded sales and assessments, not appraisals.

Is 13 Lower Alcatraz Pl, Mill Valley, CA expensive for Mill Valley?

Units at 13 Lower Alcatraz Pl, Mill Valley, CA carry a median of $1632 per square foot, 37% above the Mill Valley median of $1192 per square foot.

How often do units sell at 13 Lower Alcatraz Pl, Mill Valley, CA?

0 units at 13 Lower Alcatraz Pl, Mill Valley, CA sold in the last 12 months, out of 5 recorded arms-length sales all time. That is a turnover rate of 0.0% of the building per year.

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Assigned schools

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