Internal Auditor

Answer:
If you need to do activities related to internal audit (e.g. plan/prepare for/conduct) or you want to work and develop your career in this area – YES. Find out more in the article (although ISO 27001 – it's applicable on ISO 20000 too) “ISO 27001 Internal Auditor training – Is it good for my career?” https://advisera.com/27001academy/blog/2016/03/29/iso-27001-internal-auditor-training-is-it-good-for-my-career/

2- Market value and if I complete that, would I be certified straight away after passing the exam?
Answer: Yes, you get your certificate right after the exam.

3- Would my certificate have an expiry or renewal requirement?
Answer: No, they don't. I would recommend renewing certificate once the new revision is published.

4- Do I have to look for some specific organization with some specific accreditation to take that training?
Answer: No, no specific company.

5- If a company says they don't have A PMG accreditation, instead for ISO courses they've global recognition to accredit themselves – what would that mean?
Answer: That depends also on market you cover (local vs. global)Read the article to learn more “Qualifications for an ISO 27001 Internal Auditor” https://advisera.com/27001academy/blog/2015/03/30/qualifications-for-an-iso-27001-internal-auditor/