Capital Gains on garden development

[mullet]

I am not sure I agree with this; there is no CGT-free gain on the profit arising from refurbishment - s224(3) TCGA refers.

Good point, but this is rarely used by HMRC. They would have to successfully argue that the expenditure was incurred wholly or partly for realising a gain on the disposal. The owner (depending on the circumstances) might be able to argue that the expenditure was wholly for the refurb of a tired property, and that the increased gain was incidental. (Possibly tenuous, I know).

[Incredulum]

Indeed, but iIt's all a matter of how OP tells it.

I have planning permission to build 3 houses in the garden - renovating the existing house to create 4 houses to sell.