The main residence exemption is not the only issue that comes up with property flipping.
Tax deductions for rental properties and renovating for profit inside a self-managed super fund (SMSF) are common topics:
Can I claim a tax deduction for renovations on my investment property?
It is not generally possible to claim an upfront deduction for amounts spent on improving a property unless you are carrying on a business of buying, renovating and selling properties. If the property is held for long-term investment purposes then it is generally possible to claim a deduction for these costs over a period of time while the property is used to generate rental income.
Can I renovate a rental property owned by my SMSF?
An SMSF can renovate a property it owns as long as the money used to pay for the renovation is from money already within the fund. If the members pay for the renovation themselves (instead of using money in the fund), the renovation costs can create a contribution issue and the value could even be the improved value of the asset.
The usual restrictions around a SMSF acquiring assets from a related party should also be considered, so the SMSF should pay for all the required materials for the renovations directly (or under an agency agreement) rather than reimbursing a related party for the expense.