I have a 2.0 inverter system with two lithium battery, which I could not enjoy due to epileptic power supply and low voltage most time when power is restored.
I want to invest on solar panel to compliment this inverter system
I need assistance in making my choice. I need guidance to make the right selection on the following


1. My inverter is 12V must I buy 12V panel or I can get 24V instead what is the advantage of buying either of the two?
2. Should buy full cell or half cut
3. What brand of the panel would you recommend 4. Someone said used is better than new one is this true.

I attached sticker of my inverter and battery for clear understanding.