Dupage County, Illinois — from the county's own assessment roll.
The typical parcel above the line carries $5,841 of assessed value more than the median for like-classified land in Darien, where that median works out at about $1.63 per square foot of land.
30 days from the publication of your township's assessment roll in the local newspaper. The window is short and it is not the same date across the county. Confirm it against your own notice — a late filing cannot be cured.
Type your Darien address and you get the verdict, the comparison and the arithmetic — free, without an account. If it says there is nothing there, it says so: roughly a third of properties get told not to file.
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