In germany, if you see such a abandoned property, you cannot even ask the authority who owns it, if you have the plans to buy it (you would have to rely on local people knowing and telling you).
There are quite some neglected properties around here and the owners are away, do not care anymore and the authorities do not care as long as the low property taxes are paid. There was a case close by, where a buisness wanted to get rid of the old rotting building next to them, but could not. It went on for years. Only after the building burned down (no idea if someone helped with that), the space could be finally cleared.
So yeah, exproptiation should only ever be the last resort, but in some cases it really makes sense.
There are quite some neglected properties around here and the owners are away, do not care anymore and the authorities do not care as long as the low property taxes are paid. There was a case close by, where a buisness wanted to get rid of the old rotting building next to them, but could not. It went on for years. Only after the building burned down (no idea if someone helped with that), the space could be finally cleared.
So yeah, exproptiation should only ever be the last resort, but in some cases it really makes sense.