4820 Blum Rd Unit B is a 1,686 square foot multi-family home on a 9,583 square foot lot with 5 bedrooms and 3 bathrooms. - it last sold on July 11, 2003 for $295,000. Based on Redfin's Martinez data, we estimate the home's value is $672,969.
Multi-familyProperty Type
1949Year Built
9,583 sq ftLot Size
$399Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$672,969
$378K since sold in July 2003$13K since August
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 6.4% lower than the average sale price ($719K) of 6 comparable homes.
*Taxable value of land and structures on it ("additions") is determined regularly by local assessors and does not affect market price.
Permits
Feb 5, 2010 • Final
Building/residential/al/alteration
Remove an illegal kitchen, install an interior door, and add two attached patio covers.
ADU
Remodel
Jan 30, 2010 • Final
Building - residential re-roof
Install new composition shingles on a residential building.
Roofing
Permit history is from public records and may be incomplete or inaccurate. Redfin and its agents make no representations about the property condition or permit status. Buyers should independently verify all information.
Property details
Interior
Heating & Cooling
Heating Type: Wall Furnace
Fireplace Information
# of Fireplaces: 1
Has Fireplace
Room Information
# of Rooms: 9
Exterior
Exterior Information
Physical Condition: Average
Foundation Type: Raised W/Crawlspace
Building Style Type: Bungalow
Building Construction Quality: Average
Exterior Wall: Stucco
Property Information
Subdivision Name: LAS JUNTAS RHO
Living Sq. Ft: 1,686
Ground Floor Sq. Ft: 1,686
Building Sq. Ft: 1,686
# of Stories: 1
Legal Description: POR RO LAS JUNTAS
Lot Information
# of Buildings: 1
Land Sq. Ft: 9,583
Acres: 0.22
Zoning Code: R-7
County Use Description: DUPLEX
Utility Information
Sewer Type: Public
Water Service Type: Public
Financial
Assessor Information
Assessment Year: 2026
Public facts
Beds: 5
Baths: 3.0
Sq. Ft.: 1,686
Stories: 1.0
Lot Size: 9,583 square feet
Style: Multi-Family (2-4 Unit)
Year Built: 1949
Year Renovated: 1952
County: Contra Costa County
APN: 1592000184
Home facts updated by county records on Aug 4, 2026
Around this home
Schools
Hidden Valley Elementary School
Public K-5 • Assigned • 1.4mi
7/10
Valley View Middle School
Public 6-8 • Assigned • 2.4mi
8/10
College Park High School
Public 9-12 • Assigned • 2.4mi
8/10
Provided by GreatSchools
Lifestyle
Provided by Walk Score and Local Logic
Climate risks
1/10 Flood Factor
Minimal risk of a flood reaching the building in the next 30 years
2/10 Fire Factor
0.00% chance of being in a wildfire in next 30 years
4/10 Heat Factor
7 days above 98° expected this year, 14 days in 30 years
1/10 Wind Factor
Minimal risk of severe winds over next 30 years
8/10 Air Factor
13 unhealthy days expected this year, 13 days in 30 years
Provided by First Street
Historical weather
Martinez, CA • 94553
Average low and high temperatures (°F)
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43
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70
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49
77
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80
56
87
59
84
59
78
56
64
49
56
46
Jan
Feb
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Apr
May
Jun
Jul
Aug
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Sun exposure
89/ 100
Very good sunlight
Sunscore
There appears to be minimal shading by surrounding buildings, terrain, and vegetation.
9.9 hrs
6 hrs
JuneDecember
Provided by Shadowmap
Estimated sale price
$640,000 – $774,000
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