Bill I made the one for Salty's cage from very heavy fabric from one of the fabric stores. It's a dense black material is pretty easy to sew its custom fit and it's really really dark in there. I suggest if you're at all handy with a needle and thread that you do the same or ask a woman in your life to do it.
Gloria, BFA, adopted on Jan. 9, 2016 when she was 30 years old
. Her mom went to a nursing home.
Also have 2 cats (Rangerand Luna) and a 24 year old aquatic turtle, named Elvis.
I'm a new parront and I had to make a cover. My 30 year old BFA came with an old dome top cage. I was able to make a fitted cover that velcros in the front. Before the cover was made, I used the fabric by draping two lengths over--side to side and front to back. I used a few paper clamps to clamp the corners to keep the cats from looking under the cover. It worked well as a make shift. If you do decide to make one, Joann Fabrics sells nice 100% cotton black twill that they call "bottomweight"--figure it's for making slacks/skirts so it's heavier than cotton broadcloth and it darkens well. You can find coupons for 40 - 50% off one item right on the joann's website that you can pull up on your phone and use immediately.
I used a dark colored Polar Fleece I bought from Joann Fabrics when it was 50% off. Cost me less than $20.00 for 5 yards of 60" wide. I had them cut it in half for me (so I got 2 pieces 2.5 yards each) I brought it home and sewed a strait seam down the longest sides to join them together and just toss it over Zilla's huge dome top cage. It's dark, it's warm and it was fairly cheap & easy.
I would measure how long you need it to be front to back and side to side and then figure out how much fabric you need to buy (36" = 1 yard in length and most polar fleece is 60" wide, but it will say on the end of the bolts)
I ended up purchasing the Cozzzy Cover and except for the price I like it very much. It fits my cage nicely, is lightweight, and makes the interior of the cage pitch black when used.
I found a place that was $10+ cheaper than everyone else.