So, just like there are economic markers - re - a gallon of gas usually costs the same as a gallon of milk, and the Pizza Principle (a subway ticket and a slice of pizza cost the same in NYC) - what is the corresponding value/price indicator for the housing market? It got me thinking - if we can identify whatever that thing is - it would make it easier to see when housing got totally out of control. surely there is a correlating marker. what is it?