You can buy the paper terrain all on its own for cheap. Three sets of that and some interesting junk from around the house and you'll be set.
I have seen the terrain packs, about 10-15 US each. Thinking of grabbing a few and reinforcing it with some foam core for durability. Mixing up different ones wouldn’t be too bad would it?
Then I’m sold. Thanks for yours, and everyone else’s help.I’ll update and post some pics once I get everything finished.
I stuffed mine with foam and set a thick board at the base to make them bottom-heavy. It's important to weigh them down so they don't get knocked around.