Part of this is due to a wider variations in types and ages of homes. It is true that lower quality homes are valued less than higher quality homes. In some urban housing markets, there is a negative correlation between housing quality and age. This implies that older homes are lower quality and therefore, are valued less. The relationship between age and quality does not hold for many markets, there are plenty of examples of older homes in the Boston, Baltimore, San Francisco, New York and Chicago housing markets that are highly valued.
Maintenance has the greatest variation.
In examining the Max values, it is clear that the cost reported can include major renovation or repair. The Min value is zero for all markets - for some years, it is expected that a homeowner will not incur any maintenance costs. A number of conditions contribute to the relationship between age and quality - too many to mention here. With respect to differences in home values, the only data set that shows the predicted results is the data set of Cleveland and San Diego. As one can see, there is very little difference between the price per square foot for homes in Pittsburgh and Houston.