The article covers my advice:
If you’re a bit more adventurous, lesser-known options like Xiaomi’s Aqara, eWeLink’s Sonoff, and Ikea’s Trådfri platforms are worth a look too. In my experience, devices from these brands almost always deliver acceptable results at a fraction of the cost.
I suspect the bulk of my kit if Xiaomi/Aqara and Tradfri. It's easy enough to cobble that all together using something like Home Assistant. That said, I am still getting everything up and running after and can't for the life of me find some things. So, while I am not starting from scratch, I am having to dust off all my old know-how and that might mean I stumble across more tips but that's the key one for now.