Complex sentence: Meadowbank stadium has basketball facilities in three of its large halls, however there are almost never available to the public as they are occupied by clubs or individuals for badminton, judo, hokey, football.
Split into simpler sentences: Meadowbank stadium has basketball facilities in three of its large halls, however they are only rarely available to the public. They are usually occupied by clubs or individuals for badminton, judo, hokey, football.