1 Blackwell Drive, Watford, WD19 4HP

UPRN:100080929136Semi-Detached House3 bedsBuilt 1950-1966

FreeholdCouncil Tax: Band EEPC: D (59)

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

HP Score

/ 100

Mixed

Verdict

2 days ago

Verdict: INVESTIGATE, on a scale of Buy, Investigate, Avoid.
Mixed signals - investigate

Evidence

18 of 21 sources

Sale Estimate

£609,000

£578k - £639kHigh

Estimate

£609k

Range

£578k – £639k

Rent Estimate (pcm)

£3,000

£3k - £3k

Monthly

£3,000

Yield

6.86%

Verdict

Derived from HomePortfolio scores

1 Blackwell Drive earns an INVESTIGATE rating with HP Score 71/100. Investment score 67/100 reflects moderate fundamentals. Crime intensity is low. Walkability is limited (53/100). Flood risk is not assessed: check the Environment Agency long-term flood map before offering. Tenure is freehold. 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 covenantsHM Land Registry Price PaidPlanIt / council planning portalsOverture Maps PlacesOfsted / DfE GIAS

HP Score

71/ 100

Mixed

Investment Score

67/ 100

Moderate

Crime Score

23/ 100

Moderate

Walkability

53/ 100

Moderate

Transit & Bike

Transit 18Bike 60

Walk Score, out of 100

Opportunity

Why this could be an opportunity

Low confidence0 independent sourcesListing checked 4 Nov 2026

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

Valuation edge0/15
claims [AVM +13.8% (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 9 Oct 2026
- valuation_snapshotsestimate for 100080929136· as of 9 Oct 2026
Rental economics13.4/40
gross yield 6.9%; range width penalty ×0.90
- valuation_snapshotsrent estimate 3000/mo (range 2800-3250)· as of 9 Oct 2026· verify before relying on this
Stress margin0/30
stressed cash flow -140/mo, -5% of rent (6.75% on a 75% loan; no service charge or ground rent disclosed); fails the stress - earns nothing
- underwriting_assumptionscosts not disclosed by the advert· as of 4 Nov 2026
Seller motivationNot scored
context, not scored: 0 price cut(s), 51 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
237 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

£394,000£604,000

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£525,000

At the asking price

Monthly rent£3,000/mo

Evidenced range £2,800-£3,250

Interest rate5.4%

Loan to value75%

Cash required: £175,050
Net cash flow: £305/mo
Cash on cash: 2.1%
Score at this price: 28

After a 8% void allowance, 15% management and 10% maintenance. Lender coverage (rent ÷ interest): 1.69 - 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 100080929136Valuation edge · as of 9 Oct 2026
valuation_snapshotsrent estimate 3000/mo (range 2800-3250)Rental economics · as of 9 Oct 2026 · verify before relying on this
underwriting_assumptionscosts not disclosed by the advertStress margin · as of 4 Nov 2026
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 3000/mo (range 2800-3250)
Seller motivation could not be scored
context, not scored: 0 price cut(s), 51 days on market; homes with a cut sold 0.2-0.3pp further below the cut ask, which is not an edge

Property risk deep-dive →

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. Treat the gap to the estimate as unproven - compare recent sold prices on the street yourself before pricing an offer around it.
On later completions, homes listed below their estimate sold at the same share of the asking price as the rest.
3. 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£609,000

Rent Estimate (pcm)£3,000

Gross Yield6.86%

1y Growth+86.9%

3y Growth+2.2%

5y Growth+2.1%

10y Growth+1.8%

Last Sold Price£420,000 (2019-06-28)

View Market Details

Risk Overview

Flood RiskUnknown
SubsidenceLow
RadonLow
MiningSignificant
LandslideLow
Air QualityLow
NoiseModerate

View Full Risk Report

Planning Activity

Recent Apps

0WD19 4HP

Approval Rate

-12mo

Development

low

26/00875/DISCON
Details submitted for Condition 25 (Landscaping and Biodiversity) pursuant to planning permission 19/00778/FULM
Pending
26/00867/TCA
Works to tree T1 - Silver Birch in conservation area - 10m crown reduce by 2.5m to approx 7-8m
Pending
26/00861/DISCON
Details submitted for Condition 15.(EV Charging) pursuant to planning permission 19/00778/FULM 24/00538/VARM
Pending

View Planning Timeline

Ownership

Corporate Ownership69.7%
Overseas OwnershipNo
Lease Term Remaining-
CovenantsRestrictive
Lease TypeFreehold
Last Ownership Change2019-06-28
SourceLand Registry

View Ownership Details

Connectivity

Broadband (Standard)

10 Mbps

Mobile 4G/5G Coverage

EEThreeO2Vodafone

EV Charger

PTAL Rating

View Connectivity Map

Area Profile

Median EarningsLocal authority£37,172

Population Density4,168 /km²

Owner Occupied45%

Age Distribution

0-15 20%16-64 64%65+ 16%

View Area Profile

Schools Nearby

Oxhey Nursery School
0.2 mi
GoodConcerns
Field Junior School
0.3 mi
-
Watford Field School (Infant & Nursery)
0.3 mi
Report card2026
Ofsted no longer awards a single overall grade.
Bromet Primary School
0.4 mi
Report card2026
Ofsted no longer awards a single overall grade.

4 of 9 nearby schools with published figures were oversubscribed in 2026 - demand, not a catchment.

View All Schools

Comparables

View All

1 Blackwell Drive
-
£309k
-
41 Blackwell Drive
-
£465k
-
1 Blackwell Drive
-
£420k
-
21 Blackwell Drive
-
£430k
-

Boundary data not available for this property

No registered title polygon, building footprint, or street match for this property yet.

Why: No HMLR INSPIRE / OSM footprint / OS Open USRN match for this UPRN

Source: HM Land Registry INSPIRE / OpenStreetMap / OS Open USRN