Hello,
I read your project requirements carefully. From what I understood, you are looking for a person to maintain your website(s) and whom you can refer your clients to, as Web development is not your major business. If that's correct, I think I can be a perfect match for this position.
I understand that you don't need a person who will install a plugin and let it go. Based on that, I can say that I can modify any aspect of the WordPress website. I am working with WP for six years already and I have what it takes to do any modification on the website, in every part of the website and ensure that your WP site and all other plugins are still updateable.
When doing any change to the WordPress, I never touch the WP core code, but always creating new plugins (custom) or child-themes. And every code change is well documented and is as per WordPress coding codex.
Honestly, I am not an expert when it comes to Google Analytics, but I am able to implement your code exactly where you want it. Also, I am willing to learn more about Event tracking and various tracking methods provided by Google.
I am part of Top 3% freelancer's community (details will be provided to you on demand). Based on that, and based on my reviews here @Freelancer.com I think that you can imagine that I am the trustworthy person whom you can count for both your tasks and your clients tasks.
If you are interested, feel free to contact me, and we can discuss requirements in depth.
Thank you.
Best,
Igor