The other half of the job
Installing tags and firing events is covered in setting up Google Tag Manager. Assume that part is done and events are arriving.
What happens next is where most local businesses stall. The data lands, nobody configures anything around it, and a year later the account is full of events nobody has ever looked at.
Four settings and three reports fix that. None of them require code.
Mark your key events
GA4 collects every event you send. It does not know which ones are worth money until you tell it.
Go to Admin, then Events, and switch on the key event toggle for the ones that represent a lead. For a local business that is usually the phone click, the form submission, and the booking. Three, maybe four.
Be strict here. Marking a newsletter signup as a key event alongside a quote request means your conversion number blends a $0 action with a $4,000 one, and the blended number tells you nothing.
If the actions genuinely differ in value, you can assign each one a rough value. Even a crude estimate beats counting them as equal.
Custom dimensions, and the catch
Say your form tag sends a service_type parameter, so you know whether somebody asked about repair or installation. GA4 receives it. GA4 will not show it to you in reports until you register it as a custom dimension.
Admin, Custom definitions, Create custom dimension, and match the parameter name exactly. Case-sensitive.
Now the catch, and it is the reason this section exists.
Custom dimensions are not retroactive. Data that arrived before you registered the dimension stays invisible in reports, permanently. If you have been sending a parameter for six months and never registered it, those six months do not come back.
So register the dimension the same day you start sending the parameter. Not when you finally want the report.
2 or 14 months
The only event data retention options on a standard GA4 property. Plenty of accounts are still on the shorter one, quietly discarding last year's data before anyone thinks to compare.
Check your data retention today
This one takes thirty seconds and I find it set wrong constantly.
Admin, Data settings, Data retention. A standard GA4 property offers two months or fourteen months for event data. If yours is on two, GA4 is throwing away anything older as it goes.
Why it matters for a local business more than most: your year is seasonal. An HVAC company wants to compare this August with last August. On a two-month setting, last August is already gone.
Set it to fourteen. Standard reports still work either way, but the exploration reports, the ones where you actually dig, only reach as far back as this setting allows.
Go change it before you finish reading this. It is not retroactive either.
The three reports worth opening
GA4 ships with dozens. For a local business, three carry almost all the value.
Traffic acquisition. Where people came from, filtered to your key events rather than sessions. Sessions tell you who showed up. Key events tell you who was worth showing up.
Landing page. Which page started the visit that ended in a lead. This is the one that tells you whether a service page is earning its place, and which pages to write more like.
Realtime. Not for insight. For verification. Open it whenever you change anything on the site and confirm your events still fire.
Ignore demographics and interests for a while. They are interesting and they will not change a decision you make this quarter.
Reconcile against reality
Once a month, put the GA4 number next to the real one.
Form submissions in GA4 against actual inquiries in your inbox or CRM. Phone click events against what your phone log shows. They will not match exactly, and they should be close.
Wildly off in either direction means something is broken. GA4 showing triple your real leads usually means a tag firing twice. Showing a fraction usually means a trigger that stopped working after a plugin update, which happens more than anyone expects.
A number nobody has checked against reality is not data. It is decoration.
Common questions
Which events should I mark as key events in GA4?
Only the ones that represent a lead: the phone click, the form submission, and the booking. Three, maybe four. Be strict about it. If a newsletter signup sits next to a quote request, your conversion number blends a $0 action with a $4,000 one and tells you nothing.
Why aren't my custom dimensions showing old data?
Because custom dimensions aren't retroactive. GA4 only reports on a parameter from the day you register it as a custom dimension, and anything that arrived before that stays invisible permanently. That's why I register the dimension the same day I start sending the parameter, not when I finally want the report.
What data retention setting should I use in GA4?
Fourteen months. A standard property only offers two or fourteen, and I find accounts stuck on two constantly, quietly discarding anything older. That matters for seasonal local businesses that want to compare this August with last August. Change it today, because this setting is not retroactive either.
How do I know my GA4 numbers are accurate?
Once a month, put GA4 next to reality. Compare form submission events with actual inquiries in your inbox or CRM, and phone click events with your phone log. They won't match exactly, but they should be close. Triple your real leads usually means a tag firing twice.
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gravityGone sets up tracking, websites, and marketing automation for small businesses across Jacksonville and Northeast Florida, with websites starting at $250, no long-term contracts.
Mike is the founder of gravityGone, where he helps small businesses in Northeast Florida grow through Web Development, SEO, and Marketing Automation.
