How many lock barrels?

[pilcob]

Hi all
I recently bought a 2003 B6 S4 saloon, after 10 days of ownership the car was stolen, it has now been recovered but without the keys.
My questions are
What is involved in changing the locks and keys?
Are the glovebox and rear seat lock cylinders key specific?
How many external key barrels are there on this model?

Sorry for noob questions.

 

[Dsport]

Its not as simple as changing the lock and keys, as the key has a transponder for the imobiliser, so a new key would need to be programmed to the ecu