The property values are so depressed because the tax bills are so high. There's no reason to believe that as property tax rates fall the value of the homes would increase. When someone realizes they can get a mansion at half the price of other suburban cities and not have the ridiculous taxes and poor city services associated with the city, more people will be willing to locate to this area. As demand increases, property values increase. As the area focuses on improving schools and city services the property values increase even more, and eventually you start getting to the point of being the Grosse Pointes, a wealthy enclave that just happens to be adjacent to the city.

I'm not advocating this at all, my stance has always been a metropolitan unigov. I'm just saying that an independent "Palmer Woods" would no doubt become a successful suburban city within a decade of secession.

In any case here's some data from the 2000 Census for the area bounded by 8 Mile, Woodward, McNichols, and Wyoming:

Population: 30,850
Area: 4.68 sq. mi.
Density: 6,586 ppl / sq. mi.

Median Household Income: ~$44,000
Median Household Income [[excluding Palmer Park Apts): ~$51,000

Race:
Black - 93.2%
White - 4.9%
Other - 1.9%

Chances are that if it did become an independent enclave and city income taxes were eliminated and property taxes cut by 20 or 30 mils, the area would become more attractive to people who earn a bit more money. That would be especially true as schools and city services improved and the Livernois Ave corridor became a true "downtown"