I am looking forward to installing Ubiquiti cameras:
Unifi Protect is built into the Gateway/network controller I have (a Unifi Cloud Gateway Fiber), It's included with Unifi, so cameras and cabling are the only additional cost. All of Ubiquiti's cameras use standard Power-over-Ethernet (PoE), so don't need local power supplies, unless connecting wirelessly. Small numbers can be powered directly from the gateway, but I have a level 3 network switch which will do mine in due course. They have a good range of cameras from 'domestic' through to 'broadcast'. Most are 4k capable. I have 2TB of solid-state storage in the network controller, which they can record to, and Unifi Protect has all the usual facilities such as zones in the picture that can trigger alerts, face detection (with PTZ cameras), etc.
Down at my wife's church, I installed a UDMpro Gateway last year, with a big network switch and some new wireless access points. That can also do security cameras (and door access) as a free add-on. The UDMpro can accept fibre straight in, although their internet contract means the fibre goes int an Openreach box before they connect over cat5. To record cameras, you just add a hard disk (there's a built-in bay for this). It could do eight cameras straight in, but it's configured with a 24-port switch, and the gateway connections are used for streaming applications etc.
Both the above are network controllers, that primarily do general internet access and network management, but the security feature means only one lot of cabling and one system to look after, and some flexibility. The same cameras will do RTSP so they can be used for video feeds for the church's services too (there are quite a few elderly and housebound members, who join the services over Zoom.
The above may be a more comprehensive solution than you're looking for, but I've been using Ubiquiti kit for about 12 years or so after a recommendation from colleagues at the IT company I was then working for. I really like it, and they (Ubiquiti) still properly support the kit I originally bought, with security updates, and (last year) a major rewrite of the gateway's software. This is quite unusual.
One of the things I particularly like is that Ubiquiti don't want my data - if/when I do set up cameras, all the video data stays local, nothing passes through their servers, If I want to view footage remotely, it comes from my network straight to the viewing device, using strong encryption, but it doesn't pass through Ubiquiti.
Just a word of caution: don't buy through a well known jungle: Ubiquiti kit is very expensive there and there's a limited range. I use BroadbandBuyer (BBB), have done for years. They're not always the cheapest, but they usually are, and they carry a lot of stock. And no, nobody is either sponsoring nor giving me a kickback - as a network amateur these days, I just like the kit.
PS: This is their camera range:
https://uk.store.ui.com/uk/en/search?search=cameras . That said you'd probably get better pricing from BBB.
