Thaks Paul, that clears it up. Just got to watch whose name we put things in if we're going to be up for income tax on profits.
It is not the entity, it is what is actually being done as a question of fact.
It just happens that conducting a development in a trust is just one more indicator that helps the Commissioner spot commercial transactions.
It does not matter if you conduct it in a personal name, you should be self-reporting if speculating (purchase for resale), conducting a business or otherwise entering into a profit making scheme.
The entity used for the venture is not a magic formula to avoid tax as such.