Flat 6, 17 Knowsley Road, Southport, PR9 0BN

Flat 6 is a semi-detached house in Southport (PR9 0BN). It has a recorded floor area of 41 m² (around 441 sq ft), construction records dating it to before 1900 and council tax band A. At 41 m² this is the smallest unit on EPC record across the building (41–56 m²). The building's EPC ratings span E to C, with this unit at the top. On EPC score it ranks first in the building (75 versus a worst of 47). The latest certificate (November 2016) shows a C (score 75), near the top of the C band. When first surveyed in March 2014 the rating was D, the property has climbed 1 band since. Between certificates, wall efficiency went from Very Poor to Good, window efficiency went from Average to Good and lighting went from Good to Very Good.

Held since February 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. Its energy rating outperforms most of the postcode (better than 71% of similar EPCs). Today's modelled estimate of £117,000 is 14.1% above the 2008 sale price. On a £-per-square-foot basis, the last sale (£232/sq ft) was about 23.4% above the typical sold price in the postcode.