Hi,
in France (where we are still not JAR FCL2 compliant for helicopters):
You need to have 200 hours PIC in helicopter before doing the checkride.
You need to follow an approved ground and flight training.
You will have a checkride with an administration examiner.
You are then an IATH (deputy private flight instructor helicopter)
You will be allowed to instruct only for private pilot license.
If you are not CPL, you can not be paid for instructing.
After 100 hours of instruction, you'll become ITTH (private flight instructor helicopter), and you can deliver ratings.
If you want to instruct for CPL:
you need first to be IATH or ITTH and CPL.
you need 300 hours of total time helicopter and be approved by a civil aviation commission (usually they will ask more than 300 hours).
You will then be a deputy commercial flight instructor helicopter (ISPPH).
After a few years and probably a flight review with one of your student, and a minimum of 450 hours total time helicopter, you can be granted the full commercial flight instructor privileges.
On the job issue: not a lot of work either as CPL or flight instructor in France
Patrick