Check out the Konnected boards, you can connect wired sensors and sirens to HomeAssistant. Combine with other wireless sensors for full coverage.

https://konnected.io/

Alarm systems are often unnecessary. However, if you need one, I’d go with an old-school hard-wired system from a company like DSC. I’d avoid any “smart” devices unless you really want the convenience. For cameras, you can get a real CCTV system with beefy cameras that record to a local hard drive.

Wireless systems, like Simplisafe, are hilariously easy to bypass with even a weak radio transmitter. The devices run on very low power so put out weak signals that are easy to drown out.

Security companies will try to charge you insane monthly fees for crap you don’t need. There are companies out there that will tie into your wired system and do things like call you and the police when things go wrong for less than $20/mo. If you want the police to actually respond, I’ve heard you’ll need a camera system, otherwise they’re going to assume it’s a false alarm and get to it when they get to it, if ever. Any additional upgrades, like connecting additional smart devices to a security app managed by your provider, are generally scams imo.

Once you add networked connectivity to any of this, they tend to lock things down so they can charge you unnecessary fees to access your devices. The nice part of a dumb wired system, besides being unhackable, is that you can wire an esp32 up to it yourself and connect it to home assistant. I’d check for device compatibility with esphome before buying anything.

That’s all for actual security, though. It’s going to be overkill for 99.999% of people. The convenience of smart and/or wireless devices should not be overlooked. For something like windows, a few zigbee contact sensors from Aqara would have you covered for very cheap and the install is just sticking them on. I wouldn’t consider it a true security system, but it’s easier and more realistic. Throw in a smart camera and doorbell and you’re golden. Eufy lets you store video locally without a subscription, which is nice, but that doesn’t actually mean that it’s private.

Dog /s

It might be worth looking at the devices, but some of the ring stuff is ZigBee/wave (not sure which) and will play reasonably well with home assistant. This might offer some reuse of the equipment.

Edit: wait, no. I’m thinking of something else. Not ring.

No, I was right the first time. Older stuff usually, and of course not wifi.

https://github.com/ImSorryButWho/HomeAssistantNotes/blob/main/RingKeypadV2.md

For cameras look for NVRs that let you hook up wired cameras to. I have yet to try it but have heards that installing Frigate lets you have complete control over the recordings. Riolink and Lorex both offer systems that dont require subscriptions and supposedly let you keep your data local. I am still trying to determine what to do myself, its not a simple thing, it always seems to boil down to a matter of trust or I need to study and develop technical knowledge that I really dont have a ton of spare time for

You could put up your own home assistant compatible window and door sensors and stuff like that, but I’m not sure how it would go about calling the cops. Maybe have an integration with your phone so that if the alarm went off after like 60 seconds, it could automatically make a call to the cops or something? That’s a good question.

HomeAssistant is the only one I’m aware of.

Eufy, by Anker, is a great choice imo. They keep data local by default, no subscription required. Very minor record of controversies.