Double breeders and flights for the youngsters,then extra flights or cages for if some don't get on.It's a hobby that grows and takes over space very quickly as my misses will tell you .
It depends on what you want really atubby,a large(i don't do small cages personaly) cage will keep a couple of mules in ok but canaries,finches etc will want more space as soon there'll all be breeding or wanting to and some pairs can produce over a dozen youngsters a year hence the more space bit,have you any idea on what you want and there's plenty of experiance on here to help you. .
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