Newb Questions.

[The Lorax]

Here is the Plan:
I Want to Make a rather large Vivarium for my white lipped tree frog (possibly red eye tree frog down the line when i get one...if they can live in the same environment)... basically one as big as this one:
Front-Opening Showcase Vivarium How-To

But first off, I want to know a few things before I get ahead of myself.
A. Is a water pump / drip system necessary?
B. Would I have to change this water frequently? If so, how hard would that be?
C. Is there anything special about store bought drift wood? I don't live in a city area, and know plenty of places to find it whether it is the beach or a local lake.
D. Do the plants ever get root bound? Or do they grow so slow that it isn't a problem? Do you prune them when they overgrow?
E. Roughly how expensive is it?

those are all the immediate questions that come to mind, thanks in advance everyone for the help.