The information on this page is based on a number of underlying datasets, most of which are updated monthly. We maintain an update schedule which explains which version of each dataset we are currently relying on.
TREFARTHEN is a extended detached house, which could now be worth an estimated £215,042. It was last sold for £129,575 in October 2009, which was around 33% below the average October 2009 detached price in the Isle of Anglesey local authority area. The most recent EPC inspection was April 2009, where the current energy rating was F, and the potential energy rating was E.
Land registry data shows two sales for TREFARTHEN since 1st January 1995. The below table shows the price paid for the two sales, along with the average detached price in the Isle of Anglesey local authority area for the corresponding sale date. Both of the two TREFARTHEN sales were for below the average price. The average price is sourced from the Office for National Statistics' House Price Index (HPI).
| Date | Price | HPI Price | Variation from HPI |
|---|---|---|---|
2009 29 OCT | £129,575 | £191,990 | 33% below HPI |
1999 29 OCT | £64,000 | £71,899 | 11% below HPI |
The below graph shows the average detached house price in the Isle of Anglesey local authority area over time, sourced from the HPI. The two TREFARTHEN sales from October 1999 and October 2009 have been plotted on the graph. A line has been extrapolated to show what the value of the property might have been over time, following each sale, had it maintained the same margin above or below the HPI (as a percentage). For example, the October 1999 sale was for 11% below the HPI. So the extrapolation line tracks at 11% below the HPI over time, until the October 2009 sale, where it falls to 33% below the HPI. The line then continues to track at 33% below the HPI.

TREFARTHEN might now be worth an estimated £215,042.
This is based on house price inflation of 66%, between October 2009 and July 2026, for detached houses, in the Isle of Anglesey local authority area, as calculated by the Office for National Statistics and published in their UK House Price Index (HPI).
The 66% inflationary increase is applied to the most recent sale price for TREFARTHEN of £129,575 on 29th October 2009. For the value to have increased from £129,575 to £215,042 over the seventeen years and three months to July 2026, the following assumptions must hold true: