Happy to have a discussion with you regarding this if you like.
Insureance depends on what people required.
we hold several insurances due to the contracts we do, bu public liability at a min.
i would suggest sole trader to start, and utalise something like henry for your accounts until you get established.
And always remember, you are only ever as good as your last contract. contracting is as much of building your personal brand as it is being a good contractor.
it is hard work!

Hi Jason. Some thoughts from me based on spending most of the last 40 years in one form of consulting or another.
Insurance is an absolute must. Once, in the UK, a colleague made a cockup resulting in questions about my work. Happily I had evidence I had done the job properly.
A second instance arose from work for an insurance broker. On the cover of my report I wrote words to the effect that this was not an assessment of risks associated with earthquakes and, if the underwriters wanted such information they should consult a competent engineer. The building was effectively destroyed in the February 2011 earthquake at a cost of $40 million. I told my insurer about a potential problem. It never eventuated but I knew I had my insurer covering my back.
Whatever the work you are currently being offered make sure the PCBU puts you under its liability covers.
Are you on the HASANZ register? If you plan to be that requires you are a member of NZISM or NZSC. and you will require professional indemnity and public liability insurance. I think it is good form to be in NZISM and on the register.
If you are asked to do a piece of work but lack relevant competence say so and politely decline. Get it wrong causing harm and WorkSafe could prosecute you under section 45(b).
In 2003 I went freelance and activated a company name (Risk Management Ltd) that I had owned for some years. I felt and still feel it gave comfort to a prospective client to deal with a business. It also meant my website could be a very professional shop window. (I know it needs updating but I'm now an academic and I will update it to cover research projects.)
Beware optimism bias. For example, I can do this job in 3 days for a fee of $6,000 - but it actually takes 6 days meaning the daily rate was $1,000.
Final thought. What is your highest qualification? Does that really entitle you to call yourself a health and safety professional? Read the INSHPO Framework and see how you rate. You can study by distance learning for the postgraduate certificate at Victoria University of Wellington, then add some papers and get the postgraduate diploma, then round it off with an applied research project covering your speciality.
If you've got experience, the Master's gives you a generalist qualification and you can claim competence in some areas.
Hope this helps.

Thanks for the thoughtful response, Chris. I am a member of NZISM and I have my lvl 6 NZQA Diploma but I am not on the HASANZ register. I'll consider your advice carefully. Its given me food for thought.

Thanks for the feedback. Yes, I would appreciate being able to discuss this at some point with someone experienced and knowledgable.

I expect I will need professional indemnity and public liability insurance as a matter of course. I expect I have a way to go before I'll be held responsible for any $40 million buildings being destroyed as Chris recounts, but I certainly understand the necessity at any level.

You auckland based?
give me a call if you want 021 452 930 happy to chat

NZISM has an arrangement with Gallagher (formerly known as Crombie Lockwood), as an NZISM member you have access to this. Check out the members area of the NZISM website for more info.

Thanks, Steve. I'll call during the week. South Island based, Steve.

Remember that PI insurance includes legal defence expenses, often with a small deductible. I regard it as indispensable