The easiest way to know the state of charge is to add a Victron Smartshunt or BMV712.
This could be helpful because if you have poor solar for a few days while you are at the cabin and use more power - you will know exactly what your state of charge is on the battery and will know if/how long to run the generator.
This could be helpful because if you have poor solar for a few days while you are at the cabin and use more power - you will know exactly what your state of charge is on the battery and will know if/how long to run the generator.