I LOVE Home Assistant! Pretty much automated everything in my house. I walk around and the lights turn on with a time-appropriate brightness. They turn off when the room is empty again. I haven't touched a light switch in months. Garden irrigation is automated based on outside temperature and rainfall from my weather station. I get instant picture notifications when someone walks up to my patio or front door, and HA fakes inhabitance by turning on a couple lights randomly inside. My bedroom lights slowly dim up starting 15 minutes before the next alarm on my phone if I'm in bed (great for the winters). I'm notified when I can get free cooling or heating by opening the upstairs windows (calculated based on temperature differentials and HVAC status). I can set my alarm and view the status of all doors/windows/motion/etc. remotely. My thermostat loosens the desired temperature range when the home is empty, and tightens it back up when I return. Bathroom fans turn on when you've been on the toilet for more than a couple minutes, or when humidity spikes due to the shower being on.

There's at least a couple hundred other little things I've written automations for, and it's really nice to be able to do whatever YOU specifically want. (I even have an Android tablet mounted on the wall in my bedroom - great for setting things conveniently and it will bring up a camera stream when motion is detected in an area around the home.)

Sure the stuff requires some upkeep, but I actively enjoy that. I might have to replace a ZWave multisensor battery every year, or upgrade some configuration when a new version of HA comes out. But I always wanted a smart home I could tailor myself. Everything is local (well except Google Assistant, but that's ancillary). HA is just fantastic, and so is the community. :)