@aarenslive021608 : if i may...
for the visa fee of A$3,060, kasama na lahat dyan pati secondary applicants and dependents. so yes, for your family of 4, isang bayad lang yan.
and for your wife....actually, if you're not claiming partner points from her then she doesn't need to take the IELTS. you can just ask for a certificate of english as medium of instruction from her university. that will be enough proof of her functional english. sayang din ang matitipid sa IELTS fee. 🙂