I had some annoying hours with a few craftsmen, but I was really lucky with my property.
Population: 70,000
Location: city center, highway connection 1 km, nearest major city approx. 14 km (Bielefeld), everything available
Plot size: 1200 sqm
Is a corner plot, only 1 neighbor + dead end = super quiet for city center
Price: 110,000 euros (private sale, 2019)
I would say it is worth at least twice as much today.
I can split the plot later and you can build at least a two-family house there, no restrictions on roof shape, facade, etc.
Regards