You can either buy a complete package, or make your own. The problem with making your own is the stupid sales policies that turns camera sales into the gray market with random shit from China.

If you go POE, then buy this guy: https://reolink.com/product/rlc-423s/
Sold only direct, compatible with Synology.

Otherwise Trendnet is just about the only manufacturer that's in the retail market and not gray market. Their stuff is okay. Better than random shit from China with built-in backdoors.

Whatever you do, don't buy something from Vivotek, Dahua, or Hikvision.

Blink is a good one.

I like the Swann NVR system. HD cameras. Night

I've made sure that each system that I've built from components or each set purchased complete runs at the base of 12VDC. Some cameras operate at 24VDC or 24VAC, and I've seen some that even need 120VAC at the camera, and drop it down inside. I skip those - too many 12VDC options out there.

My systems are all plugged in to 120VAC but have a 12VDC battery that "floats" at slightly below the output of the power supply of the DVR and camera power supplies. If I lose AC (tripped breaker or PUD drops out) there is about a 1 volt dip and no interruption to the recording.
If I lose the power from PUD the notifications don't get sent, but recordings keep on trucking.
POE - That's my next build, should be pretty easy as the first two routers and modems that I just checked run on 12VDC too. As long as the phone line stays up you can still have a completely functioning system even if the power lines go down. With a backup generator to charge the storage batteries every few days you could even do this off-grid.

If you understand how to secure your network properly, then there's no problem with these types of cameras. With the right VLANs and ACLs they can try and dial home all they want and hit nothing but firewall.

I just picked this one up. They had it with a 2tb hard for 100 more but I grabbed a 4tb for 95. I'll let you know how it goes

https://www.amazon.com/gp/aw/d/B071CG4LFR