How do I set up analytics for a small NZ business website?

A small NZ business needs three things: GA4 installed through Google Tag Manager, ad pixels for whichever platforms you advertise on, and PostHog if you have an actual product beyond the website. Total software cost: $0. The catch is that the default install of all of it is nearly useless until you wire up the money event.

The stack, and why it's this one

Google Tag Manager first. Not because it's exciting, but because it's the socket board everything else plugs into. With a clean GTM container, every future tag, like a new pixel, a new tool, or a tweaked event, is a ten-minute job instead of a developer ticket. Skipping GTM and hard-coding tags into your site is the single most common mess I get asked to untangle.

GA4 through it. GA4 is the bare bones: traffic, channels, behaviour. It's free and it's the language every other tool speaks.

Ad pixels for platforms you actually spend on. Meta pixel if you run Meta ads, the Google Ads tag if you run Google. Not because the pixels are nice to have, but because the platforms' own optimisation runs on them. Unfed pixels mean your ad budget is being optimised on guesswork.

PostHog, only if you have a product. The moment people log in and do things, like a booking portal, an app, or a members' area, you want product analytics: what they use, where they drop off, whether they come back. PostHog's free tier covers most small products. For a brochure site or a straightforward store, skip it.

The part everyone skips: GA4 out of the box is a counter, not analytics

Here's the uncomfortable truth about the default install. GA4 with no configuration tells you how many people visited and roughly where they came from. That's it. It doesn't know what a sale is. It doesn't know what an enquiry is. It can't tell you which channel pays for itself, which is the only question that matters.

Analytics starts when you define conversion events, and the first one is non-negotiable: the money event. The purchase, the booking, the qualified enquiry, whatever the moment is where a visitor becomes revenue. Wired up, sent to GA4 and the ad pixels, and tested end to end with a real transaction before you trust a single number. Everything useful derives from that one event. Channel ROI, ad optimisation, email triggers, all of it.

If you do nothing else from this post, do that.

What it looks like done properly: Rembrandt

Rembrandt, the NZ menswear brand, runs on the stack above: Tag Manager underneath, GA4 configured with real ecommerce events from Shopify, and Klaviyo plugged into the same event stream for lifecycle email.

The point of that wiring isn't the dashboards. It's that every downstream decision got sharper. With purchase data flowing properly, ad spend could be judged on revenue rather than clicks. With behaviour events feeding Klaviyo, lifecycle emails, like browse follow-ups, post-purchase flows, and win-backs, fire off what customers actually did rather than a guess at a send time. Same site, same traffic, but the data finally connected the money to its causes.

That's what "analytics setup" buys when it's done with intent. Not reporting. Decisions.

/ From the workshop · MTB retail + hire · Queenstown

Bikeaholic: Revenue up 132% in two years on essentially flat ad spend.

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The discipline is the expensive part

One warning before you build any of this: dashboards are where data goes to die. The 40-widget dashboard gets opened twice, impresses nobody, and changes nothing.

The setup costs a day or two. The investment is the habit: a weekly look at three numbers, like revenue by channel, conversion rate, and cost per acquisition, and one action taken because of them. A small business that checks three numbers weekly and acts will beat one with a beautiful dashboard and no routine, every time. Tooling is cheap now. The discipline never has been.

The takeaway

GTM, GA4, the pixels you spend money on, PostHog only if there's a product. Then wire the money event before anything else and test it with a real transaction. The whole stack is free, and that's exactly why so many businesses install all of it without ever making it say anything.