Having a surveillance system is great. But only if it works. I've seen many that are essentially worthless for retrieving usable footage after an event for numerous reasons.
My 2 cents:
Find a quality contractor with good references and the ability to demo a system for you showing both day and night.
OR
Go DIY with something like Wyze
https://wyze.com/
Of course, you have to have some technical skills. And it's not even close to the quality you can get from better Dahua cameras. But it's very cost-effective.
I would only use IP/POE or HDCVI cameras.
I like the Dahua products. Especially the cameras with Starlight and integrated microphones. Like this
https://us.dahuasecurity.com/?produc...dcvi-eyeball-2
Quality of image especially at night is more important than MP.
Unless the area is very well lit you'll want high-quality IR or if you have the budget Starlight-this allows for full color with very little artificial light.
Placement is critical. Most are placed too high and too far away from important areas. You end up with tops of heads that are unrecognizable.
If you live somewhere that gets very cold or hot make sure this is taken into consideration when choosing cameras.
For added convenience cameras and an NVR with the ability to detect people and cars vs just motion is key. With just motion, unless is really dialed in you're constantly getting notification. At some point it just becomes noise and you turn it off. It's great to get a notification with a package is delivered or when the pizza guy is here.
Make sure the mobile app and desktop app are user-friendly. Some are so hard to use that finding anything is impossible.
Being able to see the cameras, having a security sign in your yard, and stickers on the windows and doors are great deterrents.
I like this one
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1