Cage size - 

Congo or Timneh Minimum size -  24W" x 24D" x 34H".  
A cage Approx 24 x 36 x 36 is a  terrific size and has room for toys.

The minimum size cage I would recommend for a macaw  is 42W x 30D x 48H 

Dometop or Playtop - 

Dometop cage is taller and has more interior room for bird and toys but has no place for a bird to play or supply food and water for a bird when out on top so a playstand with a food and water bowl can be useful

Playtop cages have a smaller interior so there is less room for allot of toys.  But with a play top there is no need for a playstand and your bird will have access to food and water when out playing.

Either cage style is fine and a personal preference depending on budget and room available for a cage and/or stand.

Cage feature considerations.

I DO NOT advise getting a Macaw cage for a Congo or Timneh baby bird.  
A Macaw cage is designed for a Macaw NOT an African Grey.  
The distance from the top to the floor of the cage is far enough that  a young Grey can injure itself seriously if it falls from the top.  Loosing grip  and falling is not uncommon for a young bird.  The bar spacing is  usually 1 1/4" which is too large in a macaw cage for a Grey.  Bar spacing  is measured from the *center* of one bar to the *center* of the next bar.  

I also Do Not recommend ROUND cages.  In my opinion they should all be 
used for plants not birds!  The sides go round and round and there is no end.  
There is no corner to get cozy and take a nap.  Just not a cage I would use 
for any bird and definitely not a Grey.

The cage should have a bottom grate that is positioned so that the bird cannot
retrieve dropped food from the catch tray.  It should also have 2 or 3 food dishes. One for dry food, one for wet foods and one for under the water bottle to catch any dripping.  This bowl should be emptied and cleaned daily to avoid bacterial infections.

Just remember your bird will be living in this cage for a very long time so this 
is a very important investment.  Take the time to look at them very closely for 
not only the safety and comfort of your bird but the ease of cleaning, feeding 
and care. 

I use indoor/outdoor carpet cut to fit the bottom tray instead of newspaper or litter.   I cut 2 for each cage so I can use one while I hose off the soiled one.

Caution: DO NOT use indoor/outdoor carpet if your bird can reach 
through the bottom grate of the cage and reach the bottom tray where you would have the carpet mat!

Stainless Steel Cages - 
I recently purchased an excellent, reasonably priced stainless steel cage.  I absolutely love it.  Easy to assemble, prompt shipping, and a very nice product.  It also comes in a powder coat for about a third the cost of Stainless Steel.   You can find the Grey Palace Cages for Greys and Macaws at - http://www.bird-supplies.net/stainless-steel-cages.htm

Perches can be purchased or you can make them yourself from  tree branches.   Before using any branches from your yard please check this site to make sure  they are not toxic to birds.   Gillian's Desk

I do not recommend Concrete perches are available to help keep your bird's nails trimmed.   Although these help keep the nails trimmed they can cause stiffness and irritate the foot because they are cold and rough.  Do not place the concrete perch as the highest perch (sleeping perch) in the cage.  If you find your bird spending too much time on a concrete perch only put it in the cage every other week.

There is a new manicure perch called a Sandy Perch.  These are wood perches with a sandy coating on them.  These will not cause foot problems as they are not cold like cement.

Soft rope makes a good sleeping perch.  Comfortable and soft on your bird's feet.  Most all my birds prefer rope perches to sleep on.  Caution: If a rope perch becomes frayed, replace it. A bird's foot could get tangled in it and cause serious injury.

African Greys and Macaws love to make soup in their water bowls.  
To avoid the possibility of bacteria from this I prefer water bottles by LIXIT or Birdie Butler.
All of my babies, both African Greys and Macaws have learned to use a LIXIT or Birdie Butler water bottle before they are weaned.  If you buy one of my babies PLEASE have a LIXIT or Birdie Butler water bottle waiting in it's cage when it arrives at your home.

Most birds will convert fairly easily to water bottles. Just attach the water bottle to the cage just above the water dish. Because they are so curious the will begin to play with it  and before long they will be drinking from it  and then the water dish can be removed.

There are other kinds of water bottles but these two are the only ones I have found  that when a bird is out it cannot either chew a hole in it or remove it  from the cage and drop it to the floor shattering it. 

Both Greys and Macaws love a variety of toys, from Acrylic toys to wooden toys.  They enjoy hanging from ropes and more challenging toys that hold treats  that they have to try to manipulate to get the treat out.

Don't over load their cage with toys but instead just keep a couple  in the cage and change them every week.  Some people say you should put  a new toy in the room near the cage for a week or 2 before putting it  in the Grey's cage because they think the Grey will freak out.   I add and change toys often when my babies are small  so they get used to different toys and change.   I also move them from a tub to a play pen to a small cage  to a larger cage etc. They have learned that change is not a bad thing.   If you keep your Grey in it's cage in the same place from the day  you get it and then 6 years later move the cage, Yes, it will get upset. 

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