your confusing "cost" with "value".... there is no "negative" land value.... its zero, the cost of the Detroit home may be $180,000 but the market value is $75,000
likewise, even in Birmingham, someone can spend millions on gold this, real fresco plaster that, peruvian granite, kokobolo hardwood flooring, etc etc... doesn't mean that whatever costs they sink into a place is going to equate to higher value... most neighborhoods are capped by what you can buy next door....
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