Another thing I would like to ask is what to do with the budgies in the aviary when there are extreme temperatures (in summer/winter)? Like in 40 degree heat with wind or in winter where there is 12/14 degrees in temperature.

I colony breed (sort of)

I have a part of my aviary with nest boxes that i can 'lock' mature budgies in during breeding season. But before i did that i had no problems at all breeding in an aviary