Welcome to the forum SteveLM
Normally rear cameras are mounted on the rear window, and i assume it too fold away in this car.
You can hard wire for 2 reasons.
1: hard wire to have your dash / console 12 V slot open for other things, most often you can do this easy by buying a female 12 V port and then wire that into a ACC fuse using a adapter. the 2 can rattle apart under the dash as plugs in this kind of socket are just friction, so you can tape the 2 together so that dont happen.
This just let your camera record while driving, and keep your dash socket free, parking guard are not supported.
The fuse you of course need for the camera will be fine if it is 5 Amps.
2: hard wire to be able to use parking guard while parked,
Here most today have the low voltage cut off on a 4 position slide switch on the hard wire kit, these are often 3 wire kits today so you need a +12 V ACC fuse a +12V always on fuse, and of course ground.
cut off voltage are most often 11.9 - 12-0 - 12.2 - 12.4 volts, the box will have a 12 volt to 5 volt converter build in as many dashcams today are powered by 5 volts using a mini - micro or USB- C plug in the camera.
But these Nextbase cameras i think are 12 Volts and so you set the cut off in the camera itself, but i am not familiar with this brand so not able to 100 % say what kind of hard wire kit these need.
Either way the camera should not drain your car battery if thisgs are working correctly, in general if you have a lead acid battery in the car you do not want to go lower than 12.2 Volts for cut off value, lower will tear 9into the lifetime of your battery CUZ lead acid batteries are not really meant to deep charge / power things for long, they are just a power storage for you to start the car, once that is done the motor will generate all the power you need + charge the car battery.
Placement or rear camera are the perpetual problem for owners of convertible cars.
