All, right now my boat has two batteries and a 90 hp merc. The first is a starting battery and the other is a group 24 deep cycle. The outboard and all electronics go to the starting battery (except trolling motor). The 12v trolling motor goes directly to the deep cycle. I have a standard 3 pole battery switch that I plan to install. However, I've just become aware of 4 pole battery switches, ACR's, battery isolators, etc. Now I'm a little confused! What is the best battery switch/charging configuration for me? I want something that's dependable and doesn't break the bank! Thanks for any info.