18a, The Market, Wrythe Lane, Carshalton, SM5 1AG

18a is a mid-terrace house in Carshalton (SM5 1AG). It has a recorded floor area of 60 m² (around 646 sq ft), construction records dating it to 1950-1966 and council tax band C. The latest certificate (August 2019) shows an E (score 54), well below the UK norm with real room to improve. The rating has held steady at E across 2 certificates since February 2009. Between certificates, lighting went from Good to Very Good; while wall efficiency dropped from Poor to Very Poor. The recommended improvements would push it to D (score 62). At 60 m² this is the 28th smallest of 50 units on EPC record in the building, where floor areas span 15–191 m². The building's EPC ratings span G to B across 50 units on file.

Across 1999–2021, sale prices on this property compounded at 9.2% per year. Today's modelled estimate of £266,000 is 19.4% below the 2021 sale of £330,000, a rare downward gap that often correlates with deferred maintenance or unfinished works. On a £-per-square-foot basis, the last sale (£511/sq ft) was about 116.3% above the typical sold price in the postcode. Last sale on file: £330,000 in November 2021. Across the public record there are 4 sales, relatively high churn for a single property. That sale was during the post-pandemic price surge, when transactions cleared materially above pre-2020 trend. It lags the bulk of the postcode on energy efficiency (less efficient than 82% of similar EPCs).