It is rather inexpensive to get a plastic chicken wire. They sell them at walmart and just about everywhere. You can use them to cover veggies and such to keep birds out. If you have a good cage you could secure it on the top. Actually the cage we have is in 2' sections x 8 sections. They come in 2, 3 and 4' heights. I bet he couldn't climb that. Be sure you don't have a collar or tags on him if he is trying to climb out. The cage makes a 4' x 4' area, which is plenty of space for Luigi to run around for the day. It will keep him from getting to stuff you leave out by accident and they can't chew the wall or baseboards either. Here's Bronxy in his (just don't fall for the sad face

)