bud the tech2 hand held diagnostic units that vauxhall/opel use cost several thousand pounds each... so i presume that you mean an opcom unit.
all you need is a good laptop with a good battery life and the purchase of n opcom unit..
opicus on here sells the units and can give you info on how to install and use the unit..
the opcam is a great bit of essential zaf owners equipment in my mind..
Drives a Zafira GSI Turbo..in Arden Blue