I also use Amazon and Camping World sites. When making my list of items to get (never-ending it seems, but fun
), I compare prices between the 2. Sometimes the disparity is huge , and I will note the prices on my list (Notes on iPhone, synced to iPad) and update the shopping carts accordingly.
For the add-on room idea, when I was tent camping, I used to have a 10x10 canopy from Gander Mountain ( Gander Mountain Combo 10 x 10 Canopy w/Mesh Sides and Wind Walls-760902 - Gander Mountain
) that had options for screens and/or wind shields to be added as "walls". We had a kitchen unit we added which had a sink, side tables, and hanging pantry for keeping stuff in. Shelves were sturdy enough for our Camp Chef oven to sit on it. Both set up/broke down quickly and had storage bags with handles win would just throw in the back of the truck.
We kept a bunch of stuff in that room - mini fridge, microwave , folding picnic table, ice-maker, etc. it became our kitchen and dining room, and worked out quite nicely for us!