shesellsseashellsair
Path to JAA,
Firstly I take it you have the right to live and work in Europe.
Need a JAA CPL (yes you can instruct on a PPL but take it you want to be paid) involves passing either the 9 (from memory) CPL or 14 ATPL exams. Pass a CPL flight test. You then need to do a JAA FI rating ( No allowance for existing holders).
As for cost depends where you do it.
My employer can help you with the first part.
See:
http://www.waaviationcollege.com.au/
Hope that helps.