Well, 30-amp is a little over 400w of 12v solar panels. So that part is easy to figure. On some of WBGO’s other solar installs they’ve used 10-gauge wire. I don’t know on yours. I’d guess they used appropriate wiring for up to 30-amps but I don’t know that for a fact.
In your case you’d need to add between 300 and 400 watts of panels and a 30-amp charge controller.
Other components like battery monitoring, inverter and batteries are all ancillary items to figure out separately.
You can put that together, find a supplier to put that together or hire someone to design it, plan it, supply it and/or install it. You’re in control.
Running the wiring is something many struggle to do. At least that part is already handled for you.
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad