If you only drive on weekends, you will not be able to do parking guard in between, that require much more power than is in the standard battery.
Though for the U1000 there is the option of the optional radar module that do indeed prolong the time the camera can do parking guard, but thats a additional cost.
No idea what data rates one of these will use, if you only have events getting saved thats probably not going to be much depending on the activity the camera see.
So say you have a regular driveway from the street, if you just drive in there, the radar module will face front and so only get triggered by you, on the other hand if you reverse into your driveway the radar will face the street, and i assume will trigger a lot depending on traffic there.
Again i must remind you i have no personal experience with these, so not aware to what degree you can tweak sensitivity to prevent too many false "alarms"
Of course if you connect to the camera again and again with the phone that will also eat up data on the sim card in the camera, but you probably soon tire of watching "nothing" that way, but like most boys a new toy are used a lot at first.
If you use motion detect, then i think it work on all cameras so it dont matter how your car are parked in the driveway.
Personally i use a CCTV camera ( mounted to my balcony door ) at home aimed at my car from my 2 floor apartment, my camera is a pan - tilt - zoom camera so i am zoomed in giving me a chance of identifying a person on the 20 M distance to my parked car.
Also my CCTV camera have SMART motion detect so it only activate on human shapes and car shapes within feet of my car, which is important as the system send notifications to my tablet on my bedside table, and i have a high price on sleep these days as often i spend 5 - 10 hours in bed spinning tossing and turning before i finally fall asleep.
In this video i am zoomed out a bit VS what i normally use on the car.
At home you should consider some form of home CCTV on your parked car VS using parking guard there.
Most cameras is hard wired for parking guard, when you stop,,,, say in your garage, there is no need to use parking guard there, in that case you long just press the power button and the camera will turn off, and when starting again everything will be back to normal and your car will be using parking guard again, say when you arrive to work the next day.
Personally i use a 1 hour timer on the system in my car that do have parking guard, this cover all my shopping, and arriving at home i just let the car do parking guard for that one hour, saving the little battery in my little car.
Doing parking guard of course put a additional strain on your car battery, these are not really meant for powering things, but if you dont go below 12.2 Volts for low voltage cut off, the impact on the car battery should be minimal ( thats about a 50 % discharged battery )
ANd of course if you use parking guard, then you also have to drive some to replenish what the system have used while parked, so these 2 things go hand in hand determining for how long you can do parking guard, also the state and size of your car battery have a say of course.
