149 Mortimer Avenue, Old St. Mellons, Cardiff, CF3 6YG

UPRN:10093732082Semi-Detached HouseBeds -Built -

FreeholdCouncil Tax: Band EEPC: B (83)

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

149 Mortimer Avenue, Old St. Mellons, Cardiff, CF3 6YG

HP Score

/ 100

Strong

Verdict

4 days ago

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

Evidence

17 of 21 sources

Sale Estimate

£352,000

£335k - £370kHigh

Estimate

£352k

Range

£335k – £370k

Rent Estimate (pcm)

£1,800

£2k - £2k

Monthly

£1,800

Yield

6.45%

Verdict

Derived from HomePortfolio scores

149 Mortimer Avenue earns an INVESTIGATE rating with HP Score 79/100. Investment score 71/100 reflects strong fundamentals. Crime intensity is low. 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 addressONS Census 2021Police.ukHM Land Registry company ownershipHM Land Registry leasesHM Land Registry Price PaidPlanIt / council planning portalsOverture Maps PlacesOfsted / DfE GIAS

HP Score

79/ 100

Strong

Investment Score

71/ 100

High

Crime Score

29/ 100

Moderate

Walkability

No data

Transit & Bike

No data

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 +4.8% (HIGH), sold-comps -9.1%, £/sqft -9.2%] → 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 12 Oct 2026
- valuation_snapshotsestimate for 10093732082· as of 12 Oct 2026
- property_comparablessold-evidence family (implied value + £/sqft): 12 comps, dispersion 9.3%· as of 1 Nov 2026
Rental economics10.7/40
gross yield 6.4%; range width penalty ×0.92
- valuation_snapshotsrent estimate 1800/mo (range 1650-1900)· as of 12 Oct 2026· verify before relying on this
Stress margin0/30
stressed cash flow -220/mo, -12% 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), 68 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 & liquidity14.7/15
404 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

£251,000£385,000

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£335,000

At the asking price

Monthly rent£1,800/mo

Evidenced range £1,650-£1,900

Interest rate5.4%

Loan to value75%

Cash required: £108,550
Net cash flow: £116/mo
Cash on cash: 1.3%
Score at this price: 25

After a 8% void allowance, 15% management and 10% maintenance. Lender coverage (rent ÷ interest): 1.59 - 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 10093732082Valuation edge · as of 12 Oct 2026
property_comparablessold-evidence family (implied value + £/sqft): 12 comps, dispersion 9.3%Valuation edge · as of 1 Nov 2026
valuation_snapshotsrent estimate 1800/mo (range 1650-1900)Rental economics · as of 12 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

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 1800/mo (range 1650-1900)
Seller motivation could not be scored
context, not scored: 0 price cut(s), 68 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£352,000

Rent Estimate (pcm)£1,800

Gross Yield6.45%

1y Growth+4.0%

3y Growth+0.6%

5y Growth+3.0%

10y Growth+5.3%

Last Sold Price£250,000 (2018-11-09)

View Market Details

Risk Overview

Flood RiskUnknown
SubsidenceLow
RadonModerate
MiningLow
LandslideModerate
Air QualityLow
NoiseWithheld

View Full Risk Report

Planning Activity

Recent Apps

0CF3 6YG

Approval Rate

-12mo

Development

low

26/02345/WTTPFP
Section fell/dismantle x1 Ash Tree- T28/177
Pending
26/02097/HSE
Proposed side single and double storey extension, including a small rear single storey extension attached.
Pending
26/01878/FUL
Proposed conversion and extensions of existing annex to form a dwelling house & erection of a detached bungalow
Pending

View Planning Timeline