Well, I used an old book case to make the brooder and it had enough room to fit a dozen almost fully matured quail chicks with enough room to wander around, jump and play in, it was a little too big for when they were day old quail chicks, so we had to be put in a box inside the brooder to be closer to the light.
For my adult quails cage we used this metal frame that was once used for those standing signs (it's bigger than I thought) that a friend gave to us. All we did was separate it, so instead of being in an 'A' shape, it was more of a 'l l' shape. All it needed was putting together, making sure it was stable, than adding the avian wire to it.
You really don't need anything fancy for quail cages except that it just encloses them from the great outdoors, and keeps them in their own mini-paradise. ^.^