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Activesingle_family

$2,858,000

298 W Duane Ave, Sunnyvale 94085

Beds5
Baths4
Sqft2,447
DOM174
No Photos Available

AddressIntel AI Briefing

Overpriced relative to size-equivalent comps and theoretical ARV in this liquefaction-prone tract. The lack of land control prevents any high-yield density expansion.

Property Permit History

DateProject TypeStatusValuationContractor
2026-10-16Engineering Project - Encroachment PermitActive - Issued--Unknown
2026-10-05Fire PermitActive - Issued$7,460Unknown
2026-09-10SolarAPP+Active - Issued$8,000Unknown

Recent Neighborhood Remodeling (Sunnyvale)

2026-10-21 • 1075 HAMSHIRE CT SUNNYVALE CA 94087
Engineering Project - Encroachment Permit
--Active - Issued
2026-10-21 • 1081 BAKER CT SUNNYVALE CA 94087
Minor Building Permit
$3,000Active - Issued
2026-10-21 • 425 S FAIR OAKS AV SUNNYVALE CA 94086
Minor Building Permit
$9,000Active - Issued
2026-10-21 • 1215 MANDARIN DR SUNNYVALE CA 94087
SolarAPP+
$32,000Active - Issued
2026-10-20 • 823 E HOMESTEAD RD SUNNYVALE CA 94087
Building Project
$14,000Active - Issued
2026-10-20 • 395 W EL CAMINO REAL SUNNYVALE CA 94086
Building Project
$20,000Active - Issued

Parcel & Zoning Info

APN--
Official Lot Sqft5,663
Zoning Code--
SB 9 StatusLikely · up to 4 units
SB 9 Block Reasons No SB 9 disqualifiers found
Development Blockers
Liquefaction
Unlock Pathways
Ministerial ADU Ministerial SB 9 Density Bonus
Entitlement RiskLow (0/100)

ADU Potential

Feasibility Score72/100
Max ADU Units2 (ADU + JADU)
Est. ADU Size1,200 sqft
Existing Coverage43.2%

Flag / irregular · Corner lot · ~80 ft frontage × 122 ft deep, a tucked-away rear unit is very private; access is typically via the pole driveway. A second street frontage lets an ADU take its own entrance and address.

Screening heuristic based on lot size, existing coverage, lot orientation, and hazard overlays. CA ADU law is ministerial statewide; verify max size, setbacks, and JADU owner-occupancy with the local planning dept.

Seller Motivation

Motivation Score30/100
Some motivation
90+ days on market

Inferred from days on market and listing-description language (e.g. "as-is", "estate sale", "motivated seller"). A screening heuristic for likely negotiability, not a statement about the seller's circumstances.

Redevelopment Potential

Redevelopment Score8/100
ClassBuilt out
FAR Utilization96% of allowed
Buildable Headroom+101 sqft

Existing home already uses most of the allowable floor area, little expansion headroom. Zoning allows roughly 2,548 sqft of gross floor area on this lot.

Screening estimate comparing existing living area to the city's single-family floor-area limit. FAR rule curated from current municipal code. Source: Sunnyvale Muni Code Ch. 19.32, Table 19.32.020 (as of 2026-06-30). Verify FAR, coverage, setbacks, and height with the local planning dept.

Hazard Snapshot

Flood Zone

X
Area of minimal flood hazard.

Fire Severity

None
Not in a mapped state fire severity zone.

Liquefaction

Yes
In a mapped liquefaction zone. May require specialized foundation engineering.

Fault Zone

No
Not in a mapped Alquist-Priolo fault zone.

Not a substitute for a Natural Hazard Disclosure (NHD) report. Zones reflect available GIS data and may not cover all localities. Liquefaction and fault flags: modified from California Geological Survey, Web Service of Official Maps of Alquist-Priolo Earthquake Fault Zones and Web Service of Official Maps of Seismic Hazard Zones (2025).

Nearby Public Schools

Elementary School

Bishop Elementary

Sunnyvale

0.4 miles away
Middle School

Columbia Middle

Sunnyvale

0.5 miles away
High School

Mission Early College High

Santa Clara Unified

2.5 miles away

School boundaries are subject to change. Nearest school distance does not guarantee enrollment eligibility. Check with the local district. Data provided by CDE.

Proprietary Intelligence

Market Heat Index

66/100

Based on recent sales velocity and local demand in 94085.

Flippability Score

20/100

Measures neighborhood renovation density vs. recent permits on this property.

Bidding War Prob.

1%

Likelihood of multiple offers based on local list-to-sale ratios and DOM.

Proforma ROI Calculator

Back-of-the-napkin deal analysis across development strategies.

Zoning allows roughly 2,548 sqft on this lot, and the default builds to that envelope. The FAR figure is a discretionary-review trigger, not a hard cap.

Median of 12 recent single-family sales in Sunnyvale (94085): $1,212/sqft, plus 5% because new houses sold at a median 1.07x their comps across 239 real rebuilds. Sized within 25% of the 2,500 sqft build, because smaller houses sell for more per foot and pricing a rebuild off them overstates resale.

Commission, transfer tax and closing. Deducted from resale before profit, so the ROI below is net of the exit rather than gross.

Interest on the purchase price for the whole project plus half the build budget, since construction draws ramp up. The default is 7% over 33 months, the median purchase-to-sale time of 239 real Peninsula and South Bay rebuilds. Set the rate to 0 for a cash purchase, or use your own lender's terms.

Hard Costs$1,375,000
New Build2,500 sqft
Total Capital Required$4,408,000
Estimated Resale (ARV)$3,182,500
Cost of Sale (5%)-$159,125
Carry (33mo @ 7%)-$699,353
Net Proceeds$2,324,023

Projected Profit

-$2,083,978
-47.3% ROI

Warning: Project is mathematically underwater.

Recent Comparables (Sunnyvale 94085)

Sized to the modelled 2,500 sqft build: sales within 25% of it. Smaller houses sell for more per foot, so pricing a rebuild off them overstates resale.

598 Madrone Ave

Sold
$3,710,000
Sold: 2026-09-25
Lot: 6,399
Sqft: 2918
$/Sqft: $1,271

552 Borregas Ave

Sold
$1,960,000
Sold: 2026-08-21
Lot: 6,334
Sqft: 2050
$/Sqft: $956

605 N Bayview Ave

Sold
$2,755,000
Sold: 2026-06-04
Lot: 7,080
Sqft: 2257
$/Sqft: $1,221

362 Stowell Ave

Sold
$2,748,000
Sold: 2026-05-05
Lot: 5,200
Sqft: 2212
$/Sqft: $1,242

248 Eureka Ct

Sold
$1,900,000
Sold: 2026-04-13
Lot: 5,750
Sqft: 1960
$/Sqft: $969

644 Johanna Ave

Sold
$2,680,000
Sold: 2026-04-08
Lot: 6,240
Sqft: 2696
$/Sqft: $994

560 Madrone Ave

Sold
$2,820,000
Sold: 2026-01-28
Lot: 6,377
Sqft: 2342
$/Sqft: $1,204

359 Stowell Ave

Sold
$2,870,000
Sold: 2025-12-04
Lot: 5,200
Sqft: 1946
$/Sqft: $1,475

557 E Arbor Ave

Sold
$2,850,000
Sold: 2025-10-15
Lot: 6,250
Sqft: 2254
$/Sqft: $1,264

310 Jackson St

Sold
$1,725,000
Sold: 2025-09-22
Lot: 6,875
Sqft: 1965
$/Sqft: $878

239 Eureka Ct

Sold
$3,010,000
Sold: 2025-08-21
Lot: 7,800
Sqft: 2240
$/Sqft: $1,344

638 Bernal Ave

Sold
$1,750,000
Sold: 2025-07-25
Lot: 6,032
Sqft: 1940
$/Sqft: $902