Walk away. The county may have reasons to condemn this property. Other considerations could be feasible but first separate the lot appraisal from the improvement appraisal.
A very good point. When you consider purchasing a property, you always look at the neighborhood and the local conditions. Ask yourself how bad a property has to be before the "condemned" sign goes on the door. Some towns, it has to be falling into the street or the playground next door before they sticker it. Others, any excuse if the right insider wants it. And the property insurance, good luck with that.
Experienced fixer-upperers know this stuff cold. A first time buyer, a minnow in a most Hobbesian sea.
I have seen people arrested and threatened with jail time for failing to demolish their condemned property. Poverty is no excuse either.