Of crucial importance is the purchaser's intention at the moment
of acquisition of the land. In Lionel Simmons Properties Ltd v CIR
 53TC461. Lord Wilberforce said at p.491:
"Trading requires an intention to trade: normally the question to be asked is whether this intention existed at the time of the acquisition of the asset".
It is therefore often necessary to demonstrate an intention to trade at the moment of acquisition.
That moment is, in land transactions, the moment of exchange of contracts for purchase and not the moment of completion.