SKIP TO CONTENT
S.LOWENSTEIN
DEAL INDEXBUILDINGSMARKETSTOOLSGUIDESWHOCONTACTVALUATION_
VALUATION_
DEAL INDEXBUILDINGSMARKETSTOOLSGUIDESWHOCONTACTWHAT'S IT WORTH? →
THEME
DEAL INDEXBUILDINGSTRACK RECORDMARKETSMARKET REPORTTOOLSGUIDESDEAL ALERTSWATCHLISTWHOVALUATIONCONTACT
(323) 944-2221@SHAYASELLSLA
© 2026 SHAYA LOWENSTEIN · LYON STAHL INVESTMENT REAL ESTATE830 S PACIFIC COAST HWY, SUITE D-200, EL SEGUNDO, CA 90245SHAYA@LYONSTAHL.COM · DRE #01942326
BUILDINGS/10227 MASON AVE
/// BUILDING FILE · ROLL 2025

10227 MASON AVE.

Chatsworth, CA 91311 · APN 2741-025-038

/// WHERE DO WE REACH YOU?

ONE EMAIL, USED TO KEEP THIS LIST AND TO TELL YOU IF A WATCHED BUILDING LISTS OR SELLS. UNSUBSCRIBE ANY TIME.

UNITS

50

BUILDING SF

33,080

SF / UNIT

662

YEAR BUILT

2013

BEDROOMS

94

BATHROOMS

81

USE · CODE 0500

5+ UNITS

/// ASSESSED VALUE
LAND$3,543,386
IMPROVEMENTS$9,423,155
TOTAL$12,966,541
LAND BASE YEAR2025
OWNERSHIP TENUREUNDER 2 YEARS

PROP 13 ASSESSED VALUES — USUALLY WELL BELOW MARKET ON LONG-HELD BUILDINGS.

/// LAST TRANSFER
RECORDEDSEP 30, 2024
EST. PRICE (2024)$12,966,541
EST. $/UNIT$259,331

PRICE ESTIMATED FROM ASSESSOR REASSESSMENT AT SALE — NOT A VERIFIED CLOSING PRICE.

/// RENT CONTROL

LIKELY EXEMPT (NEW CONSTRUCTION)

Built 2013 — buildings under 15 years old are exempt from AB 1482; the state cap applies once the building turns 15.

AB 1482 VS RSO →INFERRED FROM PUBLIC RECORDS — VERIFY WITH LAHD / ZIMAS BEFORE RELYING ON IT.
/// ZIP 91311

Recent sales nearby.

ADDRESSSOLDEST. PRICEEST. $/UNITUNITS
10507 MASON AVE→NOV 2024EST.$1,560,000$780,000UNITS222332 LASSEN ST→MAY 2024EST.$1,100,000$550,000UNITS220010 HAWKS HILL RD→APR 2024EST.$4,995,000$2,497,500UNITS210547 VARIEL AVE→NOV 2023EST.$1,188,000$594,000UNITS211450 POEMA PL→OCT 2023EST.$22,771,989$392,621UNITS5811451 POEMA PL→OCT 2023EST.$6,204,000$387,750UNITS1611500 POEMA PL→OCT 2023EST.$34,530,000$359,688UNITS9611503 POEMA PL→OCT 2023EST.$10,137,000$389,885UNITS26

PRICES ESTIMATED FROM ASSESSOR REASSESSMENT AT SALE (ASSESSED VALUE DEFLATED 2%/YR) — NOT VERIFIED CLOSING PRICES.

/// COMPARE

Buildings like this one.

ON MASON AVE · ZIP 91311

10507 MASON AVE→2 UNITS · BUILT 1947 · DUPLEX

SIMILAR SIZE AND ERA IN 91311

10243 TOPANGA CANYON BLVD→55 UNITS · BUILT 2023 · 29,041 SF10247 VARIEL AVE→32 UNITS · BUILT 2021 · 27,697 SF9825 TOPANGA CANYON BLVD→31 UNITS · BUILT 2004 · 17,686 SF
EVERY BUILDING IN 91311 →
/// COMMON QUESTIONS · 10227 MASON AVE

The short answers.

Is 10227 Mason Ave rent controlled?

Built 2013 — buildings under 15 years old are exempt from AB 1482; the state cap applies once the building turns 15. This is an inference from public assessor records, not a determination — confirm the certificate of occupancy date with the LA Housing Department or ZIMAS before you rely on it for pricing or notices.

How many units does 10227 Mason Ave have?

County records list 50 units at 10227 Mason Ave, classified as 5+ units across 33,080 square feet of building area, averaging about 662 square feet per unit. Unit counts on the roll can lag permitted conversions and unpermitted additions in both directions.

When was 10227 Mason Ave built?

The assessor roll gives a build year of 2013, which is after the October 1978 RSO cutoff. Age drives more than character here: it sets rent-cap exposure, seismic retrofit obligations, and what a lender will underwrite.

When did 10227 Mason Ave last sell, and for how much?

The last recorded transfer was September 2024, at an estimated $12,966,541 — about $259,331 per unit. That price is estimated from the Proposition 13 reassessment recorded at sale, not a verified closing price, so treat it as a close approximation rather than a confirmed figure.

What is 10227 Mason Ave assessed at, and is that what it is worth?

The current assessed value is $12,966,541 ($3,543,386 land, $9,423,155 improvements). Assessed value is not market value. Under Proposition 13 it resets only on a change of ownership and then climbs about 2% a year, so a long-held building is often assessed far below what it would trade for.

How do I find out what 10227 Mason Ave would sell for today?

Public records give you the frame — units, size, age, assessed value, when it last traded — but pricing needs in-place rents, expenses, and the condition of the units, none of which appear in county data. A broker valuation puts closed comps and a rent survey against the actual rent roll. Shaya Lowenstein does that free for LA multifamily owners, typically within 48 hours, with no obligation to list.

/// OWNER READING
WHAT IS MY BUILDING WORTH? →SELLING WITH TENANTS IN PLACE →HOW LA RSO WORKS →

Own this building?

FREE, CONFIDENTIAL VALUATION FROM CLOSED COMPS — 48H TURNAROUND.

WHAT'S IT WORTH_TALK TO SHAYA →

NOT SELLING? GET DEALS LIKE THIS FIRST →