Cash flow on your primary residence?

[Dee Danner]

Our family is looking to purchase our first home. We plan to be in our new place for at least 5 years (we have a 12 year old and want to stay in place until he graduates). Do you use the same criteria (like 20% below market, potential rental cash flow, etc.) for purchasing your primary residence as you do for your investment properties? I'm finding properties that meet our family's needs but when I do the numbers renting the property would not cash flow.