Property taxes should be included in your expenses.
Monthly Expense Totals
If you are using "Monthly Expense Totals," make sure you include a prorated amount of your annual taxes. For example, if your annual property taxes are $1,200, you should include $100 in your monthly expense total to account for the expense.
If you are a PlannerPlus member using "Budgeter," you can enter property taxes as a line item under Home Related Expenses. You can decide if you want to enter the expenses as monthly, quarterly, or annually. You can also choose to make this expense deductible to more accurately model tax liabilities.