The "add a Room" is a Dometic Cabana which were sold
as an option on Rpod trailers. Dometic stopped making them a few years ago and surplused off the stock. i picked mine up from Ebay for about $150 when the originals went for about $600. Check with an RPod dealer to see if they have any old stock.
Originally Posted by cmartin748
Loooks like a great time. Love the "add-a-room" on your camper. May I ask where you bought it?