Are you looking to just chage flashlight batteries or to have a larger system for lighting,radio,TV ,small items and cell phone charging.
You could charge flashlight batteries from your auto for DAYS without needing to start the car and your reply indicates you have plans
to use an inverter in your auto (maybe for fridge,etc?)
If the auto has a planned use the I would use an 18 amp hour to 50 amp hour (typical auto battery size) and use it in HOUSE
for lighting and small devices and charge it ,with inverter and standard 12 v charger, while the auto charges the fridge...
You don't really need solar for a small house battery to charge small batteries and do simple small devices. In fact most places only
have 5 hours of good sun and way less when weather is the root of your power outage. Solar is good,but not the ONLY answer.
I would start with a 50 to 100 amp hour battery with a battery box fitted with cigarette sockets and USB outlets ,plus maybe a small inverter
to run LED lighting,TV,FAN etc. and add a 120 volt charger (up to 6 amps is good) to charge the battery and then an auto inverter to power
the larger items (1200 to 1600 watts is better than too small) and while running for the fridge (1 to 2 hours out of every six) it can also
charge the house battery...no solar needed..
OK,your turn..What is you vision?