I have double CN and I'm interested in making the bottom half into a jungle gym/ climbing toy for my girls. I've seen pictures of people using wine racks with modifications (such as rope ladders and tunnels) What should I look for if I want to purchase a wine rack to use for that? or would it be best to make my own wine rack and modify as I go? What kind of wood would be best and what should I use to keep it all together (nails, screws, woodglue)? Any suggestions for fun things to put on the jungle gym itself? A completely different idea would be to make my own cat tree style play surface, which would include levels to climb on instead of having to walk tight ropes etc. This might be better for my older girls, but wouldn't be as mentally stimulating. In this case would I use a wood base and seal it off for easy cleaning? what would I use to finish the wood in that manner?