For this issue the legal test is:
1. A self-employed person has the onus of clearly demonstrating the basis of his or her net income. This includes demonstrating that the deductions from gross income should be taken into account in the calculation of income for support purposes.
2. The party needs to prove that the expense deducted was necessary to conduct business.
3. Where significant amounts of untaxed business income are used for payment of personal expenses, the law provides for “grossing up” business income to place a spouse’s real income on a par with what it would be in a salary context.
4. For example, common expenses that may legitimately be deduced for income tax purposes, but personally benefit the party include expenses for car, home office, travel and entertainment.