Advantages of a company include that:
liability for shareholders is limited
it's easy to transfer ownership by selling shares to another party
shareholders (often family members) can be employed by the company
the company can trade anywhere in Australia
taxation rates can be more favourable
you'll have access to a wider capital and skills base.
Disadvantages of a company include that:
the company can be expensive to establish, maintain and wind up
the reporting requirements can be complex
your financial affairs are public
if directors fail to meet their legal obligations, they may be held personally liable for the company's debts
profits distributed to shareholders are taxable.