29 Castellain Mansions, Castellain Road, London, W9 1HE

UPRN:10033580304Purpose Built Flat2 bedsBuilt 1900-1929

LeaseholdCouncil Tax: Band FEPC: D (68)

Data freshness:Listing· freshPlanning· 4mo agoOwnership· freshEPC· 6mo agoRisk· 5mo agoConnectivity· 1mo agoSchools· 1mo agoAmenities· 2mo agoArea· Census 2021

29 Castellain Mansions, Castellain Road, London, W9 1HE

HP Score

/ 100

Strong

Verdict

yesterday

Verdict: INVESTIGATE, on a scale of Buy, Investigate, Avoid.
Strong fundamentals; flood risk not assessed

Evidence

19 of 21 sources

Sale Estimate

£972,000

£924k - £1.02MHigh

Estimate

£972k

Range

£924k – £1.02M

Rent Estimate (pcm)

£4,150

£4k - £5k

Monthly

£4,150

Yield

4.74%

Verdict

Derived from HomePortfolio scores

29 Castellain Mansions earns an INVESTIGATE rating with HP Score 85/100. Investment score 67/100 reflects moderate fundamentals. Crime intensity is low. Walkability is excellent (93/100). Flood risk is not assessed: check the Environment Agency long-term flood map before offering. Tenure is leasehold. Every figure here comes from the live HomePortfolio API; anything it does not publish is left out.

Key SourcesEPC RegisterPortal listingsOfcom Connected NationsOfcom mobile coverageMarket estimates (third-party AVM)HM Land Registry sales matched to addressDefra strategic noise mapping, England Round 4 (Contains Defra data © Crown copyright and database right 2023-2024, Open Government Licence v3.0)Walk ScoreONS Census 2021Police.ukHM Land Registry company ownershipHM Land Registry leasesHM Land Registry Price PaidPlanIt / council planning portalsOverture Maps PlacesOfsted / DfE GIAS

HP Score

85/ 100

Strong

Investment Score

67/ 100

Moderate

Crime Score

16/ 100

Moderate

Walkability

93/ 100

Excellent

Transit & Bike

Transit 52Bike 75

Walk Score, out of 100

Opportunity

Why this could be an opportunity

Low confidence0 independent sourcesLead to verifyListing checked 4 Nov 2026

This rests largely on a single source. Treat the score as a prompt to investigate, not a conclusion.

Check before relying on this score: leasehold with no service charge disclosed - the stress test assumes GBP 0. It ranks after every home whose inputs are verified.

Valuation edge0/15
claims [AVM -8.0% (HIGH)] → measured edge +0.00pp of the ask; on later-registered sales an AVM discount carried no edge and a sold-evidence gap at most +0.5pp
Market estimate used (HIGH confidence) · snapshot 13 Oct 2026
- valuation_snapshotsestimate for 10033580304· as of 13 Oct 2026
Rental economics0/40
gross yield 4.7%; range width penalty ×0.84
- valuation_snapshotsrent estimate 4150/mo (range 3750-4500)· as of 13 Oct 2026· verify before relying on this
Stress margin0/30
stressed cash flow -1,509/mo, -36% of rent (6.75% on a 75% loan; no service charge or ground rent disclosed); fails the stress - earns nothing; leasehold with no service charge disclosed - the stress assumes GBP 0
- underwriting_assumptionscosts not disclosed by the advert· as of 4 Nov 2026· verify before relying on this
Seller motivationNot scored
context, not scored: 0 price cut(s), 46 days on market; homes with a cut sold 0.2-0.3pp further below the cut ask, which is not an edge
- portal_listingsprice_changes + first_published_date· as of 4 Nov 2026
Risk & liquidity14.6/15
258 sales/12mo in area; valuation range width 10%
- property_intelligencetransactions_12mo

4 of 4 components scored. Ranks on gross yield, the stress margin, risk and disclosed facts. A pricing claim earns only its measured edge: today 0 for the market estimate and at most +0.5pp for sold evidence. The score itself is not yet checked against the outcomes of homes it scored.

Economics

What happens to your money

Price sensitivity

£787,500£1,207,500

The same scorer re-run at hypothetical asking prices, holding rent, comps and listing history constant. Not a prediction of what the seller would accept.

Your assumptions

Purchase price£1,050,000

At the asking price

Monthly rent£4,150/mo

Evidenced range £3,750-£4,500

Interest rate5.4%

Loan to value75%

Cash required: £365,050
Net cash flow: -£671/mo
Cash on cash: -2.2%
Score at this price: 15

After a 8% void allowance, 15% management and 10% maintenance. Lender coverage (rent ÷ interest): 1.17 - below the usual 1.25 test. These are your assumptions, not evidence: only the pre-filled rent and price come from the record.

Evidence

Where every number comes from

valuation_snapshotsestimate for 10033580304Valuation edge · as of 13 Oct 2026
valuation_snapshotsrent estimate 4150/mo (range 3750-4500)Rental economics · as of 13 Oct 2026 · verify before relying on this
underwriting_assumptionscosts not disclosed by the advertStress margin · as of 4 Nov 2026 · verify before relying on this
portal_listingsprice_changes + first_published_dateSeller motivation · as of 4 Nov 2026
property_intelligencetransactions_12moRisk & liquidity

Sold comparables in depth

Risks

What could kill this deal

Score confidence is low
largely a single source - treat the number as a prompt, not a conclusion
Rental economics needs verification before you rely on it
rent estimate 4150/mo (range 3750-4500)
Stress margin needs verification before you rely on it
costs not disclosed by the advert

Plan

Before you offer

1. Get two written rental appraisals from local lettings agents.
The rent estimate rests on area-level evidence, not lettings on this street.
2. Commission a full structural survey, not a basic condition report.
The score prices market evidence, not the fabric of the building.

Every step above was generated from a specific gap or flag in the evidence - no generic advice, no invented tasks.

Valuation & Market

Sale Estimate£972,000

Rent Estimate (pcm)£4,150

Gross Yield4.74%

1y Growth-8.0%

3y Growth-4.5%

5y Growth-0.6%

10y Growth-0.3%

Last Sold Price£1,050,000 (2015-10-19)

View Market Details

Risk Overview

Flood RiskUnknown
SubsidenceSignificant
RadonLow
MiningUnknown
LandslideLow
Air QualityLow
NoiseLow

View Full Risk Report

Planning Activity

Recent Apps

0W9 1HE

Approval Rate

-12mo

Development

low

26/07418/FULL
Refurbishment and internal reconfiguration of the existing single dwelling, including the adaptation of the existing basement vaults beneath the private forecourt through the lowering of the existing vault floors to provide additional habitable accommodation, external works comprise the installation of two new timber sash windows within the existing front lightwell, the upgrading of the existing timber sash windows with slim-profile double glazing, the replacement of the existing front entrance door with a timber door to match the character of the property, alterations to the front lightwell including Yorkstone paving, and associated internal and external works.
Pending
26/07389/NMA
Amendments to planning permission dated 04 June 2025 (RN: 25/02022/FULL), NAMELY, amendment of Condition 4 to correct the property address from 9 Aldridge Road Villas to Flat 1 5 Grittleton Road.
Approved
26/07431/TELNOT
Removal of six antennas and associated ancillary equipment; installation of six antennas at a height of 53.5m AGL on the existing three 3.75m support poles, one 0.3m dish and associated ancillary equipment; upgrade of the equipment within the existing cabin and development works thereto.
Approved

View Planning Timeline