Hi Ian,
Like you, I'm not a coder. I barely have rudimentary css skills.
I've run into your situation many times. This is my perspective:
Despite not being a programmer, I can find and read the template (.tpl) files. If I spend some time, I can begin to recognize the purpose of various parts of those files, and even the need for seemingly redundant files that relate to the same basic site functions but are often located in different folders in the template folder. I can also begin to see the logic. Then, with a healthy nod to syntax, I start to "comment out' or even modify some parts of those files. With a little trial and error, i can usually accomplish the changes I want to make.
I think this is the limit of personal customization of the Abantecart platform for non-tech people. Anyone can do anything within their skill limitations.
If you reach your skill limit, and that limit is beyond the basic capabilities provided by the Design>Layout feature of the Admin control panel, you have already entered the world of developers who do read and write code.
If you dive in deep enough to ask a specific question about a specific part of a specific file to accomplish a single specific goal, you can usually find the answer in the Documentation or on the AC youtube channel or by searching this site. If not, ask the specific question on the forum; it usually gets answered.
If you dive past the Control Panel but ask only a general question about how to change an entire page, IMO, you've entered the universe of paid services. You can pay someone to modify your site or you can buy an extension that has your desired changes already built-in, but you can't expect the AC devs or any other contractor to customize your site for you at no charge.
That's my experience.
This is meant to be an encouraging reply: the reason that you push your own boundaries is that pretty much anyone can do this if they spend a little time. If i can do it, anyone can.
You either spend your own time, or buy someone else's.
If you can cut and paste code into files, you're already halfway there.
Good luck! HTH.
