I am going to be a first time bird parent in a couple of weeks. I'm adopting 2 three-year old linnies. They are a bonded pair, male and female. I am reading madly to learn as much as possible. (I've already learned tons here, thanks) I will appreciate all your help in answering my questions. One is the size of the cage. I know as big as possible is best, but what is a good size to start with? How many perches? Thank you.