If you are looking for a cheap and easily expandable cage for your hedgehog, you may want to look into making your own out of plastic storage tubs. Plastic storage tubs are light weight, which makes them easy to move and clean, and are easily expandable. Below you will find some directions that I used when I built a cage out of 2 storage tubs.
First you will need to find large clear plastic tubs. Look at Wal-Mart, K-mart or even your local hardware store in their storage container aisles. While those that have lids which are not removable are fine, try to buy one which you can take the lid off easily. Plus all the additional items to put in the cage.
Next, decide how you want the tubs connected. For example, do you want the tubs to sit side by side, end to end, or even corner to corner (see diagram below). Depending on the placement of the cages, will determine what type of tube you will be using to connect the tubs.
You may or may not need a lid for you hedgehog. It will depend if you hedgehog is a climber and how tall the sides of the tub are.
From each end and 1" from each side, use a pencil to mark the lines to be cut. Then, use a drill with a 1/4" bit to cut holes in the corners of the lines so that wire
cutters can be inserted. Then use wire cutters to cut out the middle of the lid. After that, cut insect screening to the correct size to fit the hole. Hot glue each corner down for stability, then come back and glue down the sides with one continuos bead of glue. Repeat for the other lid.
This type of lid should give your hedgehog plenty of air circulation, keep them in their cage, and it doesn't look too bad.
Cutting the holes
I have heard of so many people breaking or cracking the tubs when they try to cut in to them with a knife. To prevent the plastic from cracking, use a hair dryer to warm the area that you plan to cut. Then use a drill to make a small hole to start the cut. For ease of use, I have found that a Dremel (hand rotary tool) works the best with a cutting bit on it. Others have used wire snips, soldering irons/wood burning tools, etc. to cut the plastic. I recommend cutting the hole a little small at first then shaving the sides down until the tube you are using to connect the tubs with fits snug.
Once the holes are cut, ensure that there are no rough edges, clean the inside of the containers thoroughly, there will be bits of plastic inside the containers that needs removed to prevent a hedgehog from accidentally ingesting some. Place the containers in the location you want your hedgehog's new home, insert the tubes, and arrange the new cage in a fashion that your hedgehog would like.
Below is a picture of a cage built out of 2 plastic storage containers and a 1 foot length of PVC pipe. The space between the cages makes a great storage spot for treat containers.
A few additional notes, if you want to attach a water bottle to the
cage, drill a hole at the appropriate height on one side of a
container, put the nozzle through the hole and attach the bottle to
the outside of the cage. This will help keep the water bottle from
being climbed on and knocked off the cage.
Also note that if you would like an entrance to the cage that the hedgehogs can get in and out of at will, I have found that using a ferret T shaped tube with a bubble plug, works great. I line the tube with a piece of vellux to prevent hedgie feet from falling through the holes in the tube.