Building a Home with Full Apple HomeKit Integration — Looking for Best Practices and Recommendations

You will first need an Apple Home Hub, an Apple TV or HomePod. See : Set up your HomePod, HomePod mini, Apple TV, or iPad as a home hub - Apple Support. Disregard the mention of an iPad being a Hub. It no longer can on the latest software. If you’re buying these products for the first time be sure to get the latest generation so it can support forthcoming software updates.

You need a home wifi network (avoid Dual Bands) and a primary Apple ID Account to use the home App to control Home.

You need to purchase smart accessories that support Apple HomeKit: Home app - Accessories - Apple . Look through these products and see what appeals to you then read up on each one. Again, be sure to get the latest generation of products as they change over time. It’s not possible to go through each of these products to know which is the latest. This is something you can research on your own. Most can be purchased anywhere.

The products you choose is a personal preference. I like Philips Hue for lighting. I like the Ecobee thermostat. Do your research. Watch YouTube tutorials, etc.

More: Create scenes and automations with the Home app - Apple Support

There’s much more to learn and you will learn as you go. As to hidden wiring. You’re basically looking at using wall outlets or smart bulbs screwed into existing light fixtures or lamps. Or smart plugs that use a wall outlet. Or installation of smart switches that turn on lights. Depending on what you want to automate.

also be mindful that some homekit devices use Bluetooth rather than wifi, which means that the range is much smaller so those devices needs to be placed closer to the homekit hub.