Sorry I can't give you any links, having real problems with my broadband connection.
If you go the the EASA website, google for EASA 145, that document tells you what you need with regard to personnel, their qualifications, tools equipment etc etc. You would I think go to the CAA if in the UK for the approval, if you go to the CAA website there is info on there as well.
Or the easiest thing may be to contact your local CAA surveyor for guidance. Unfortunately with EASA at the moment, you will not get the same answer from 2 different surveyors. Confused, they certainly are!
What has been mentioned above is 'Grandfather Rights' you basically retain them when the rules and regs changed, as said, once you leave or move elsewhere you can not take those rights with you, if you have a B1 or B2 licence with type ratings you take those with you. Not cheap though, I've recently converted my BCAR to an EASA licence and it wa almost £500. It's going to cost me some more yet as I have just completed all the modules to remove the restrictions from the licence, that's another £90 and then another £90 to remove them from each type.