Mr Fritz and Hans Solo live in cages like the one pictured left. These come in many sizes. The Marchioro Tommy 120 is the largest. Bigger is Better when it comes to Bunny Homes.
How I Solved The Door Problem
To solve the door problem (the door is hinged at the bottom, making it difficult for a rabbit to hop in and out
Simply unhinge and remove the door to let the rabbit out, then flip it arround hinge at the top of the cage, secure at the bottom when bunny returns home
I like cages with the plastic bottom. They are easy to clean and won't harm the bunnies's feet as some wire-bottomed cages do.
Another cage solution is to use a puppy pen or exercise pen. (ex-pen) These panels fold and can be adapted to fit any space.They come in different heights. Be sure to get one tall enough to accommodate a jumper.
There are some "soft-sided" types available. I wouldn't recommend those for rabbits.
If you have space, the ex-pen enclosure can also be used with the above mentioned cage. Keep all the rabbit equipment in the cage, litter box, etc and leave the door open, making a nice play area for your bunny.
If you're handy, you can build your own rabbit enclosure. Velvet and Miss Bea share a divided bedroom. The wire and wood divider fits snug against one wall dividing the room in half. (like this)
Two hinged doors open in the front.
Be sure to use wood that is untreated and safe for chewers.
Here is Velvet in her pen. A child's plastic swimming pool contains her litter box and hay. This makes for an easy clean up. Miss Bea, her roomate has the same set up on the other side of the divider