How to connect an outdoor camera? LAN, power or battery

how do you actually connect the PoE cameras outside? Do you have connectors directly on the cables or have you had boxes installed on the wall outside or is the cable laid directly onto the cameras?

Reolink would not be in my shortlist. POE cameras from AXIS, Hilvision, Dahua… You should control lighting via motion detectors or presence detectors, light barriers, etc. Your budget is good for cameras. Where do you want to record?

The easiest option is Synology or Qnap.
Personally, I prefer Synology in terms of usability.
I would record for a longer time. 24 hours is too little.
3 days to 1 week. Storage space is not expensive.
With 4 cameras and 4k, you must choose a corresponding NAS. Especially since you will probably want to use it for other things as well.
Take a 48-port switch right away. You can connect the NAS with more than one port.
Cameras and recording device should be in a separate network. At least virtually (VLAN).
The NAS then in both networks. For this, you need a router and switch that support VLANs.
Or the NAS takes on this task. Meaning router and switch for the normal network and one switch for cameras and one port from the NAS.
The NAS must then act as a router in the camera network.
The data should also be backed up externally. Otherwise, they might be lost in case of theft.
If you only want the NAS for the cameras, you could also take a network recorder from e.g. Axis. They also come with a switch.