You can run hot and cold water to almost every area of the house because they use pressure to flow, but sewer uses solely gravity.

What can you tell me about buying a home with 2 gravity fed furnaces in working order?  

Housing prices are so over-inflated it's not even funny.I would not buy in this market....wait for the inevitable correction and then pounce.There is no new normal.....Real estate is like gravity.......

Water hits the siding, runs down wall, hits the concrete, and gravity takes it inside.

To put it simply, long term appreciation is where the big bucks are made in RE, and prime CA locations are the center of gravity for that to happen. 

MAYBE if it was lying on its back so gravity was on your side.

I look at it similar to a law of physics like gravity....It almost can't not happen.But I was wrong once......

If the whole system is such a frail little whisper than it NEEDS to come falling down, if that's it's gravity than it needs to hurry up and happen.

Unstable ground under and gravity is the blame.

So far, at least, the median listing price continues to defy gravity.