Inherited a Coleman 7AMP PWM Controller & 3-4 Panels

capeacock

I picked up an off grid trailer (30') in Northern Ontario, I discovered 3 solar panels connected up to a box on the trailer, and when I opened the box, I discovered two Coleman 7amp Controllers, which in checking are PWM.  The controller is connected to one battery, and the trailer connected to the other battery (no solar controller connected to it, suspect previous owner moved the trailer cables between them).  I am assuming these are "house" batteries. I am suspecting the panels are 30 or 50w panels.

I am looking at adding/upgrading this system.  My goal short term is to have the solar charge the batteries, and have the trailer connected to the batteries using DC (all together without having to move cables around).  I have a ground zero yeti 400 which will run the TV for the interim, and lasts a weekend.

I have read that using golf cart AGM batteries are better in series.  Where I am lost is if I replace this current Charge Controller with another PWM controller and connect it to the batteries, can I connect the trailer to the batteries or the load side of a controller, do I purchase a MPPT controller and if so can I connect the current panels?  Trailer has LED bulbs, fridge is on propane, water pump is DC, same as lights, and spark for fridge, and furnace.

my goal next year, be able to plug the trailer into an AC pure sine inverter (3000W or 2000w) to run if needed the TV and AC, charge phones/tablets/laptop (if required).  Most trips are 2-3 days with a few times a year where a week is spent (and assuming the batteries will charge up full over a week).  I have a Honda EUI3000 generator.

I am new to off grid and solar, and hoping to gain some insight into what's needed and if I buy stuff in the short term, can I re-use it next year?

thanks,