[2068]
...
It’s quite possible that the owner could have spent hundreds of thousands renovating that property over the more than twenty years
It was a "do it upper" - the owner runs a plumbing and gas fitting business, so I'd guess that he either did a lot of the work himself or got others to help at mates rates.
But even so, on the South Coast there are still plenty of houses with a similar price trajectory, admittedly most starting from a slightly higher baseline.