It is no secret that the upfront costs of having a corporate trustee are considerably more than having individual trustees. But in the long run, corporate trustees can be well worth the costs. The upfront costs of setting up a corporate trustee seem to far outweigh any immediate benefits. In the long run however, there are many benefits, including greater flexibility in the types of benefits that can be paid, perpetual succession, administrative efficiency, flexibility in estate planning, and a reduction in the risk of mixing fund assets with personal assets.
Costs for setting up a corporation as the trustee for you trust will include legal fees, administrative expenses, taxes, stamp duty, ASIC fees and ongoing payment to the corporate trustee. These will vary of course.
See this article for more of the benefits of having a corporate trustee for your family or discretionary trust.