Flat 4, 17 Wales Avenue, Carshalton, SM5 3QN

Flat 4 is a semi-detached house in Carshalton (SM5 3QN). It has a recorded floor area of 30 m² (around 323 sq ft), construction records dating it to 1991-1995 and council tax band A. At 30 m² this is the 2nd smallest of 6 units on EPC record in the building, where floor areas span 25–53 m². The building's EPC ratings span D to C, with this unit at the top. On EPC score it ranks first in the building (77 versus a worst of 60). The latest certificate (September 2022) shows a C (score 77), near the top of the C band. When first surveyed in January 2009 the rating was D, the property has climbed 1 band since. Between certificates, wall efficiency went from Very Poor to Good and lighting went from Very Poor to Very Good.

Held since January 2008 — that's 18 years off the open market, well above the local norm. That sale landed at the peak of the pre-credit-crunch market, which is a useful reference point when interpreting the price. At 30 m² it sits well below the postcode median (71 m² across 24 EPCs), making it one of the more compact homes locally. Across 2005–2008, sale prices on this property compounded at 8.1% per year. Today's modelled estimate of £184,000 is 36.3% above the 2008 sale price. On a £-per-square-foot basis, the last sale (£418/sq ft) was about 33.3% above the typical sold price in the postcode.