Flat 21, 8 Sail Street, London, SE11 6NQ

UPRN:10093378151Flat/Maisonette1 bedsBuilt -

LeaseholdCouncil Tax: Band DEPC: B (88)

Data freshness:Listing· freshPlanning· 4mo agoEPC· 6mo agoRisk· 5mo agoConnectivity· 1mo agoSchools· freshAmenities· 2mo agoArea· Census 2021

Flat 21, 8 Sail Street, London, SE11 6NQ

HP Score

/ 100

Strong

Verdict

2 days ago

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

Evidence

20 of 21 sources

Sale Estimate

£350,000

£332k - £367kHigh

Estimate

£350k

Range

£332k – £367k

Rent Estimate (pcm)

£1,700

£2k - £2k

Monthly

£1,700

Yield

5.67%

Verdict

Derived from HomePortfolio scores

Flat 21 earns an INVESTIGATE rating with HP Score 84/100. Investment score 74/100 reflects strong fundamentals. Crime intensity is low. Walkability is excellent (96/100). 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 covenantsHM Land Registry leasesHM Land Registry Price PaidPlanIt / council planning portalsOverture Maps PlacesOfsted / DfE GIAS

HP Score

84/ 100

Strong

Investment Score

74/ 100

High

Crime Score

17/ 100

Moderate

Walkability

96/ 100

Excellent

Transit & Bike

Transit 81Bike 79

Walk Score, out of 100

Opportunity

Why this could be an opportunity

Low confidence0 independent sourcesLead to verifyListing checked 5 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 -2.9% (HIGH), sold-comps -6.2%, £/sqft -6.2%] → 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 10093378151· as of 13 Oct 2026
- property_comparablessold-evidence family (implied value + £/sqft): 10 comps, dispersion 4%· as of 1 Nov 2026
Rental economics4.8/40
gross yield 5.7%; range width penalty ×0.91
- valuation_snapshotsrent estimate 1700/mo (range 1550-1800)· as of 13 Oct 2026· verify before relying on this
Stress margin0/30
stressed cash flow -399/mo, -23% 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 5 Nov 2026· verify before relying on this
Seller motivationNot scored
context, not scored: 0 price cut(s), 37 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 5 Nov 2026
Risk & liquidity14.6/15
117 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

£270,000£414,000

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£360,000

At the asking price

Monthly rent£1,700/mo

Evidenced range £1,550-£1,800

Interest rate5.4%

Loan to value75%

Cash required: £117,300
Net cash flow: -£38/mo
Cash on cash: -0.4%
Score at this price: 19

After a 8% void allowance, 15% management and 10% maintenance. Lender coverage (rent ÷ interest): 1.40 - clears 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 10093378151Valuation edge · as of 13 Oct 2026
property_comparablessold-evidence family (implied value + £/sqft): 10 comps, dispersion 4%Valuation edge · as of 1 Nov 2026
valuation_snapshotsrent estimate 1700/mo (range 1550-1800)Rental economics · as of 13 Oct 2026 · verify before relying on this
underwriting_assumptionscosts not disclosed by the advertStress margin · as of 5 Nov 2026 · verify before relying on this
portal_listingsprice_changes + first_published_dateSeller motivation · as of 5 Nov 2026

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 1700/mo (range 1550-1800)
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£350,000

Rent Estimate (pcm)£1,700

Gross Yield5.67%

1y Growth-0.2%

3y Growth-6.4%

5y Growth-2.5%

10y Growth-1.0%

Last Sold Price£332,000 (2017-03-14)

View Market Details

Risk Overview

Flood RiskUnknown
SubsidenceSignificant
RadonLow
MiningUnknown
LandslideLow
Air QualityLow
NoiseModerate

View Full Risk Report

Planning Activity

Recent Apps

0SE11 6NQ

Approval Rate

-12mo

Development

low

26/03163/LB
Application for Listed Building Consent for internal alteration including removal of internal partitions and a door, reposition of staircase and amending of kitchen layout.
Pending
26/AP/3171
T1 Beech - Section fell to ground level; tree is right up against a brick wall and approximately 5.0m in height with a 4.0m crown spread.
Pending
26/AP/3167
T1A London Plane (x1) - Reduce the crown back to previous, most recent points of reduction, with retention of knuckles. By 5m in height and 3m in width to a final height of 16m and a final width of 5m.
Pending

View Planning Timeline