I have a large (1040 amp hour) battery bank in my trailer. The only wires touching my batteries are the interconnecting 4/0 cables. I have one positive and one negative cable coming from my batteries that go to bus bars. All 12 volt trailer/inverter connections go to those bus bars. It is the simplest way to wire a battery bank and with the proper sized wires for the length involved, there will be no issues with voltage drop/loss.
Since Facebook was mentioned. Here is a link to a Facebook post I made with a full description of my system including pictures and a wiring diagram.
https://www.facebook.com/groups/9172...7588748956282/