Costs of babies (weekly/monthly)
- nappies, anywhere from $10 packet Coles brand (that last 1.5 weeks) to $30 for a box of Huggies (that last a couple of weeks)
- milk, breast milk doesn't cost but not every can cope breast feeding twins. Formula can cost $19-$28 per tin for newborn.

Costs of kids
- food
We spend $250 a week on groceries for a family of 6 (2 adults, 3 kids, 1 baby) that's for everything.

- school
Lower income earners can apply for 'school card'. For us that means in the public school system we don't have to pay school fees.
For uniforms I buy the big W generic school clothes that are about $8 per item.

Realistically it's not easy. But if it's what you want then there is support to help.

We live on about $800 per week for 6 people (a little bit more at the moment while getting baby bonus).
I don't have twins myself. But providing for 4 kids while on government benefits. It's still worth it for me.