Which of the following would NOT contribute to a reduction of a property investor's tax liability?

The option regarding profit upon the sale of a property is the correct answer because profits realized from selling a property can actually increase a property investor's tax liability, rather than reduce it. When a property is sold for a profit, the difference between the selling price and the purchase price (known as capital gains) may be subject to taxation. This means that rather than providing a deduction or reduction in taxes, capital gains can lead to an increase in the amount of taxes owed.

In contrast, the other options represent legitimate deductions or expenses that can lower taxable income. For example, property repairs are often deductible as they are considered necessary maintenance costs that help preserve the value of the property. Property tax deductions allow investors to deduct the amounts they pay in property taxes from their taxable income, which can effectively lower their overall tax liability. Similarly, interest on loans in regard to financing the property can be deductible for mortgage interest, also promoting a reduction in taxable income.