If the activities you are planning do not fall within the exemptions and the activities are not fulfilling the primary purpose of the charity, then the activity may be undertaken within a trading subsidiary owned by the charity.
The Charity Commission advise trustees to consider the risks involved in the trading and to channel risk-bearing activities and trading to generate income through a trading subsidiary. In particular, the trustees should not put the charity’s assets at risk through its trading activities. If the taxable profits from a trading subsidiary are transferred to the charity under Gift Aid they are not liable to tax. Similarly it may suit the charity to channel all activity liable to VAT through a trading subsidiary, potentially allowing the charity to remain unregistered for VAT.