I had a nice ficus as well as a small schefflera tree. I would buy the plants from a nursery (ask there if they put anything on the plants) then rinse the heck out of them in your bathtub and repot them with new soil.

Substrate can be as simple as paper towels. I wouldn't recommend newspaper as it doesn't absorb water from the dripper nearly so well. You could also just use potting soil.. your cham will spend very limited time on the floor.