I woudn't have a top opening door, especially for the buttons!! Now I have had some like that for coturnix, and they didn't escape much.
I have a neat idea for a cage (should patent it
but I think it's borrowed
)
Make a thing like a bookcase, I'm planning on 4'wide by 5'-6' high by 1'deep. (This is for
button cages, but you could modify it to fit the coturnix.) Anyway, divide each 'shelf' in half, so that each side is 2'wide. Each shelf would be 1'high. So you would have
(with a 6'high 'shelf') 12 button cages that are 2' x 1' x 1', perfect size for a pair. Each shelf would have wood sides, top, and bottom. Then I will take a piece of coroplast or more wood, to make a 'splash guard' in the front and back of the cage, about 3" high. This would keep their bedding in the cage, where it belongs.
Depending on where in your home you plan to put it, you could either have the doors in the front or on the sides, just make sure
(if on the sides) that you make it hinged so you don't have to open every cage at once.
In your case, I don't know how many coturnix you have, but you could make one or two shelves as full length, giving you a 1' x 4' cage. Good size for 4-5 coturnix.
Other modifications: You could also (for the coturnix) make the height of each cage higher, and put some 1/4" hardware cloth (raised) in the bottom, with a pan of shavings or whatever underneath. Coturnix really smell, I would use pine pellets
Of course, you could make all 3 sides wood, and just the front wire. I would use 1" wire, so you can use the pop bottle waterers for them. This would give them more floor space. You could also get some cup feeders (like those used for parakeets) instead of actual feeders, this would also take up less room.
ETA: Buttons do better on solid floors, since their feet are so tiny. I would use 1/2" wire for the floor of the coturnix cages.
You could also use the 1/2" wire for the sides of the cage, then just cut a spot out for the waterer.
The 'splash guard' would also be good for when your buttons hatch their babies
I have 3 of the mamas wanting to set on eggs, so yours could be 'broody buttons' as well!!
Especially if you keep them in pairs!