Plumbob

Hi We emigrated to Australia and lived there for a few years then moved back to the UK. I never got my plumbing license at the time as I was a little bitter about the thought of spending even more money and going back to college to get qualified for something I was led to believe I would be qualified in when I arrived. I got a Heating job with a company and didn't need to go back to college but the money wasnt great. My question is if we move back does any Plumbers/Heating Engineers on here know what is involved exactly to get a plumbing license and how much it costs if we move back over? Thanks