Most of the dragon 'kits' I have seen are too small for a single adult dragon. That and they often contain 'junk' which is either totally unnecessary, or actually dangerous to have in a dragon take. In the long run, you end up paying more, instead of saving money on kits.
There are tons of PVC, plastic or resin type cages that have fixtures pre installed (or can be asked for as an option) which are big enough for bearded dragon adults. For a single adult, you need at least a 4'x2' of floor space, though height can be tween 18-24". These are stackable, lightweight and durable...but you still have to buy the bulbs, substrate and other contents.
If money isn't a problem you can buy large wide log/wood sections to act as basking areas, (make sure the diameter or width of the basking area is at least as wide as a dragon...5" is a good size to go with. A few hides can be of any material as long as it is big enough for your dragon it get in, turn around and come out. Just make sure there is no cedar of any kind in the cage..or pine. These can be found at any petstore or aquarium store (large flat rocks can be used as basking areas too, but if you stack them, make sure they are secure and on the floor of the cage so your dragon can't knock them over or dig underneath them and get hurt.)
Check the cages/enclosures section under the Business tab above for a list of cage makers in the US. You can also check the enclosure forum for ideas.
It is far cheaper to build your own out of melamine or plywood and I am sure if you email BDLvr and ask nicely, he will share how he made his cages. If you are like me and have mediocre or completely lack any skill in building stuff with wood (I can design them..can't cut a straight line if my life depended on it, then again, sometimes can't even draw a straight line even with a ruler) maybe you have a friend or relative who will be happy to build your cage for you. I had the cage below built for me by a family friend...all I did was pay for the wood and gave him a bottle of rye to show my appreciation..unfortunately don't have the cage anymore...had to give it and the dragon inside away 6 years ago....and my own attempt to duplicate it, isn't anywhere near as nice...

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PHLdyPayne