NOI and inclusion of Capital Expenditures

[Autumn Burkett]

I am trying to understand why a calculation for capital expenditures would not be included as an expense in calculating the Net Operating Income for a property. I have been using a calculation of approximately $200/ month for a single family home as one of my expenses included when analyzing properties. However, I am finding that most resources note that you should not include cap ex in your NOI. At the end of the day, you are going to be paying for cap ex, why not include it as a monthly expense? This can make a huge difference in calculating annual cash flow, cash on cash return, and cap rate. What am I missing here?