i'd say it's a bit exaggerated to say "every" nieghborhood you've ever seen.
It's true that wild variations are not exactly uncommon in older mixed
neighborhoods (e.g., 1920s-era) where you'll have a mansion next door to a
small, simple house, but it's not common in newer neighborhoods, where most
of the houses are pretty much the same.

where i live (Atlanta), wide variations within a single neighborhood are one
of the surest signs of mortgage fraud (and we have the highest rates in the
country). There was an article in the paper about a year ago about a woman
who had wondered why there was so much variation in her neighborhood.... she
ended up uncovering a big ring.




I personally have better things to worry about. Thats why I would like
an
HOA to worry about it for me. Take some time to consider why you dont
see
blocks with wildly varying home values.


Every
neighborhood I've ever SEEN (while shopping for houses) has houses of
WILDLY
varying market values. It's not unusual at all to see the lowest market
value house on a block be some fraction of the highest market value house
on
the block.