According to the IRS, if you are renting a property without the intent to make a profit you can deduct rental expenses up to the amount of your rental income. You could not deduct a loss in the current year and could not carry forward a loss to subsequent years.
First you deduct the allocated real estate taxes, mortgage interest, and casualty loss and direct expenses.
.If the total of these deductions equals or exceeds the gross rental income then you must stop here. No other deductions are allowed.