Build Cat Tower I Want To Build A Cat Tower And Could Use Help?

I want to build a cat tower and could use help? - build cat tower

I have my first cat is a monster climb. I went to Petsmart and Petland and they want almost 200 for the one I want. I prefer to build and that's where I need help. Who knows if there a site that explains how to build too. I'm sure it's fairly easy to build, but I still can with a lid Lil help run an obstacle. I do not know what to use for the oval, so it is not certain what material was used to for this piece. In addition, a preference that I use wood. I think working the pen, but no idea if it's expensive or not. If anyone knows what Wood is the cheapest and fastest way would be great.