How good are the rear cameras for the next base units.
And do you need a larger SIM data card
My solution with our two vehicles is to use repurposed, secondhand 212 and 312WG units, not as designed but placed on the rear windows. 2 K, 1920 x 1080 30 fpm units.
These cost me circa £20, on respectively Gumtree & eBay. In both cases I replaced the inbuilt batteries as these were decidedly tired, I recall these cost me about £10 each. The SD cards I got another eBay deal on decent new Samsung 64 GB, a job lot costing me effectively under £1 each.
The set up works well but has the typical direct sunlight glare issues these low spec units are prone to exhibit. I have not tried any polarising filtering.
My thinking apart from minimising the spend was that any rear dashcam has to be rear mounted to get any meaningful wide enough field of view,
A warning label of "camera recording", helps them being as needed as the tailgating did that motivated their adoption!