[rlh1957]

The prep is roof penetration wiring down to the point where solar charge controller and inverter goes. Some Cougars at least 2019/2020 have the OTG solar prep. This allows three different plugs to be hot from the inverter when connected. The roof connectors and the side portable solar plug are all Zamp. If you put in the Zamp or let the dealer install Zamp... Most will elect to change to solar connectors that are the industry standard and not a Zamp that tries to create a proprietary plug, which is usually wire reverse polarity. The basic Zamp that Keystone planned for gives you a good battery charger. You need 4 to 6 AGM or Lithium batteries to really put out 110V from the inverter and be able to operate for hours or overnight. The stock solar ready cable that Keystone puts in Cougars from the roof isn't very heavy and will need to be upgraded for anything over 500W solar output and that it the top of that gauge cable. At least the cable is there so you so pulling new cable is easier. You can call dealer and get a quote on equipment plus labor.
Also contact another solar installer to see what they can offer. You will have to have your list of what you hope to accomplish and operate with your solar system. It isn't one type fits all.