I’ve finished wiring Google Analytics (GA 4) into a React‑based site (deployed on Vercel).
Before declaring victory I need to **prove that every page view and custom event really reaches GA**.

From Googling and reading Stack Overflow I see quite a few “verification” options:

1. **[Chrome DevTools – Network tab](https://developer.chrome.com/docs/devtools/network/)**  
   Look for `/collect` (UA) or `collect?v=2` (GA4) requests.

2. **[Google Analytics Debugger Chrome extension](https://chrome.google.com/webstore/detail/google-analytics-debugger/jnkmfdileelhofjcijamephohjechhna)**  
   Console shows events; handy in local dev.

3. **[Google Tag Assistant (legacy)](https://support.google.com/tagassistant/answer/10044221)** *(or the new [Tag Assistant Companion](https://support.google.com/tagassistant/answer/10125983))*  
   Badge lights up when a tag fires; can record sessions.

4. **[GTM Preview / Debug mode](https://developers.google.com/tag-manager/preview-debug)**  
   Shows all tags, triggers, and data‑layer pushes.

5. **GA4 UI tools**  
   • **[Debug View](https://support.google.com/analytics/answer/7201382)**  
   • **[Real‑time report](https://support.google.com/analytics/answer/9264745)**  
   Built‑in UI; latency sometimes masks problems.

6. **[Trackingplan](https://trackingplan.com/)**  
   Third‑party QA platform that automatically crawls pages, captures events, and reports schema mismatches or missing events across environments.

What I’ve tried so far
----------------------

* DevTools confirms `collect?v=2&t=page_view` on route changes.  
* GA4 Debug View sometimes shows nothing for ~20 seconds, which makes me wonder if I’m missing hits.  
* Tag Assistant recording shows the events but I don’t know if that **guarantees** they reached GA servers.  
* I haven’t set up Trackingplan yet—curious whether it adds value beyond the above.

What confuses me
----------------

* Are **some methods better suited to staging vs. production**?  
* Does GA4 sample or delay real‑time data enough to give false negatives?  
* Can Trackingplan (or similar) catch issues the free Google tools miss—e.g., missing parameters, wrong event names, consent‑mode quirks?

**Question**

> For day‑to‑day QA of GA4 instrumentation, which of the approaches above (or others I missed) provide the most *reliable* signal that events are truly stored in GA?  
> *What are the trade‑offs (latency, sampling, cost, ease of use) and when would you choose one over another?*

Any guidance or war‑stories appreciated!