Comprehensive health and travel insurance that meets NZ Immigration requirements

I'm going with a Working Holiday visa to NZ for a year. I'm starting to look for health (or travel) insurance in my country (Chile) to leave with a little more peace of mind.

When I was looking for insurance, the first result got me to this company and it says

[...] a low cost and comprehensive health and travel insurance that meets NZ Immigration requirements.
It is compulsory for Working Holiday Visa holders coming to NZ to work in retail, fruit picking, or hospitality industries to provide evidence of comprehensive travel insurance while they are in New Zealand

I haven't realized it was compulsory to have health insurance to go. And sure enough, I went and read the inmigration website once more

To be eligible [...] hold medical and comprehensive hospitalisation insurance for the length of your stay

even though in the actual visa I got it didn't refer to health anywhere, except maybe

You may also be asked to provide evidence of any other conditions that you were required to meet as part of the working holiday scheme under which you submitted your application.

So, ok, I have to get health insurance. But that leaves me with a whole lot more of questions:

• Does anyone know if they'll check it coming in our out of the country?
• And what is considered "comprehensive hospitalization"? Should I worry about how much does my insurance cover to know if NZ considers it "comprehensive" and let me enter the country?
• Does it matter where I get my insurance, Chile or NZ (don't even know if I can do that from Chile)? I mean, can I arrive in NZ and ask for insurance there or won't I even be allowed out of the airport without one?
• Does the insurance has to be for the length of my stay? I don't even have return tickets so I can't really give a date. Most insurance companies in Chile give and estimate for max of 60 days. Can I get and insurance in Chile for those 60 days and look for other insurance in NZ after those 60 days?

I know those are a lot of questions and I'm supposed to post one question per... well, post, but they all relate to the exact same thing: what does "comprehensive hospitalization" means? What are my limitations or exact requirements to decide for an insurance plan or the other? I don't want to pay for a plan and then realize it isn't really what NZ wants and kicks me out...