First of all, I'm very excited to find this forum. I finally convinced my mom to let me buy a ball python and I am getting a 5 month old one with a cage and total set up for $60, which is a great deal. I don't really want to keep it in a 20 gallon tank for too long, as a much bigger one that it can live in forever would be much more ideal right now. So I started building one and am currently waiting on the plexiglass to continue. I have some questions about building it...

My cage will be 3 feet tall and 45 inches long with side lengths of around 2 feet.

1.) Is there some sort of material I should coat my wood with to ensure it is safe for the snake? I will be completely sanding the back wall of the cage but the bottom is completely smooth. Just wondering if there is something I should coat it with in case there is any chance there are chemicals in it?

2.) What should I put in my cage to make it realistic? What is the best bedding? I would like to put a waterfall in one corner but I'm not sure if it is OK to do with a ball python. I would like to spend less than $100 on the inside of it and can add things as I go, but for starters what should I have in addition to a big water dish, heating pad, and a hideaway. Would a ball python climb in a tree at all?

3.) Is plexiglass the best option or is there something cheaper?

That's all I have right now. Thanks in advance!