Lots of people seem to refer to City-Data.com as a source for statistics, photos, weather, maps, etc. for just about any city or village in the U.S.
One popular feature of the site is the "Top 100 Lists." These indicate the relative ranking of places (mostly those of at least 2,000 people) in a variety of categories.
For example, according to City-Data.com:
Village of Cahokia, IL. Ranking = #12. Ratio = 1.27. Median Income = $31k. Median House Price = $39k.
Glasgow Village (unincorporated pocket), MO. Ranking = #46. Ratio = 1.45. Median Income = $36k. Median House Price = $52k.
City of Dellwood, MO. Ranking = #47. Ratio = 1.46. Median Income = $43k. Median House Price = $63k.
City of St. John, MO. Ranking = #77. Ratio = 1.53. Median Income = $38k. Median House Price = $58k.
City of Bellefontaine Neighbors, MO. Ranking = #93. Ratio = 1.56. Median Income = $40k. Median House Price = $62k.
What these ratios basically mean is that in those North County and Metro East suburbs, it should only take about a year-and-a-half (on average) to earn enough to pay for your house.
Of course, just because houses are affordable relative to the average income of the town, doesn't necessarily mean these are good places to live. Indeed, all of these munis are what might be deemed 'transitional' - income, on average, is going down, as are housing sale prices, as better-off (mostly white) old timers move out to St. Charles County (or the Shiloh/O'Fallon IL area in the case of Cahokia), and are replaced by typically much less affluent African-Americans.
Why is that? Well, it can be explained by Isla Vista also coming out as #17 on the list of Youngest Residents (median age = 21.1) and #3 on Highest Percentage of College Students (76.6%).
Isla Vista is the home of UC-Santa Barbara. It's not just a college town - it's basically a college campus/suburb of the much larger seaside city (with similarly costly houses) of Santa Barbara. That explains the statistical anomaly pretty well.
Strangely, both Clayton, MO (#47, 70% with BA, median income $64k) and Richmond Heights, MO (#86, 57% with BA, median income $50k) appear on this list as well.
Why? Each of those towns hosts a men's prison with a population greater than the regular resident population. In Ina, it's the Big Muddy Correctional Center, for example. Still, it's kind of funny to read: "For every 100 females there were 874.2 males."