We are thinking we will build something like this I don't plan to breed and have two birds and occasionally baby sit two others. It would be nice if I could keep them all together (not too worried about disease as they are all from the same original flock) I am very much still learning so don't want to kick myself about the design later! Mostly wondering if I should enclose the back half and if I should put shelves for them or perches. (American fantails). And if so what's a good size.