Property taxes should be included in your recurring expenses.
If you are using the Basic Budgeter, 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 (one-twelfth of $1,200) in your monthly expense total to account for the expense.
If you are a PlannerPlus member using the Planner+ 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.