A CSP place is subsidized by the goverment, so your tuition fee would be below $8000 per year for commerce students taking the normal 48units of credit. Within a CSP place, you can choose to defer the payment through a HECS loan or pay upfront and get a 20% discount.
A DFEE place has no subsidies. You pay the full tuition of the course just like international students. This is a lot more expensive. I don't know the exact cost for commerce, but expect it to be over $15000 per year.