An intention to make a profit supports trading, but by itself is not conclusive.

Is the asset of such a type or amount that it can only be turned to advantage by a sale? Or did it yield an income or give 'pride of possession', for example, a picture for personal enjoyment?

Transactions that are similar to those of an existing trade may themselves be trading.

Was the asset repaired, modified or improved to make it more easily saleable or saleable at a greater profit?

Was the asset sold in a way that was typical of trading organisations? Alternatively, did it have to be sold to raise cash for an emergency?

The way the sale was carried out

Was money borrowed to buy the asset? Could the funds only be repaid by selling the asset?

Interval of time between purchase and sale