Been doing this for several years in my house.

My home office is in the basement, gets cold in the winter. Immediately when motion is detected in the master bedroom in the morning (and it’s a weekday and the outdoor temperature is below a certain amount) the space heater will automatically kick on for 1 hour to warm the room up.

I also have a Zigbee switch setup right at my desk that I can hit to pop it on again for a 1 hour interval during the day if I want.

My wife puts up with my HA habit, but even I knew that cameras were something to approach delicately. What we sort of fell on - and she is ok with - the following:

Outdoor cameras (doorbells and such) - fine. Adds to security.

Garage camera to check to see if we accidentally left the garage door open while we are away, she was ok with that.

Interior cameras in spaces that generally are not occupied (we have a 5BR house) were ok.

That got us through for a while. But then life circumstances changed and it evolved into us being away a couple weeks at a time on a regular basis. After a couple circumstances where she was worried maybe our house was getting broken into, we agreed to an interior camera in a main living space - but it had to be something that could be visibly seen as to whether it is on or off, and set to automatically go into “off” when either of us are home. We picked a camera from EZViz for that. When you switch on privacy mode the camera lens rotates back into its own body and it’s obvious from just looking at it. HomeAssistant controls automatically putting it to and out of privacy mode.

This made me think — is it maybe a security thing he is going after? Like a cheap, makeshift alarm? If so, just steer the conversation into a security panel instead.

5 years ago, Home Assistant really wasn’t “in reach” for most other than application developers / IT folks. It was beyond what your average person could have reasonably grasped.

But one of the more recent versions in the past few years, they really did work a lot on UI and usability, web interfaces for most things, etc. So it is very much a great mainstream solution. I have it in our main home and our vacation home, and I never worry about either no matter where I may be.

Don’t worry too much about HA geeks on internet forums in terms of cloud-connected vs. not-cloud-connected devices. Generally, things that don’t have a dependency on the cloud will be a bit faster/more responsive, and you won’t have the business risk of the company behind it killing the product / going out of business and shutting off their servers (i.e.: my Dropcam from 10 years ago is facing that fate soon).

So look for devices without a cloud dependency, but IMO don’t bend over backwards. You want a decent indoor/outdoor camera system with some AI features? Might be that Nest or Ring would work just fine for you. If you read people here too long they’ll tell you that you have to run your own power-over-ethernet cameras to a Frigate NVR recorder that you run in a Docker container on your Proxmox server … yadda yadda yadda … you get the point.

Sometimes the best devices for you are just going to be cloud-connected and there isn’t much you can do. You need to be conscious of the business risk, though - read about the history of the Wink Hub platform for an example of how things can go poorly. Or Philips Hue terminating all cloud support for the 1st gen hub for their light bulbs.

The other thing that is great about Home Assistant, is that because it’s had such a hardcore software developer following - there are integrations for practically any home automation device out there you can think of. Heck, even our SleepNumber bed … as soon as we got it on the network, it found it and suggested a pre-built integration. Now our house knows when the spouse and I both hop into bed, and it automatically shuts off all the lights, locks all the doors, etc.

ME: Used HomeSeer 20 years ago, with X.25 switches. Gave up on HA for many years, came back when SmartThings launched (knew one of the founders) and it was a great platform until Samsung bought it and then it declined over many many years. Now on Home Assistant and extremely happy with it, one of the most powerful platforms out there IMO and always evolving. Fortunately, all of my SmartThings switches and sensors worked so I didn’t lose money on those.