Right, there are non-investment related values to a house for most people. Kids friends in the area, nice neighbors, the landscaping you did last year, etc. So

Right, there are non-investment related values to a house for most people. Kids friends in the area, nice neighbors, the landscaping you did last year, etc. So even if you couldn't sell and recoup your mortgage, doesn't mean the value of your house is worth walking away from. On the other hand, investment properties are almost entirely dollar based. Which is why (in theory), banks require a higher down payment on them - to get you invested.