Kumamoto is barely finished rebuilding from the last quake, you can still see cracks in structures as you drive down the road. This is really horrible; not to mention the city is already beginning to depopulate as the youth move north to Fukuoka.
Apparently the declining population and younger people not wanting to live in their parents' rural countryside home is having a significant effect on property values.
If you're willing to move to depopulating areas houses cost a little kinda everywhere.
In Puglia, Italy, in my in laws village (8'000 people), you can buy a freshly renovated, rather huge house for 50k, and you can likely find livable ones, not renovated at the 10-15k.
In US, in many rural areas you can buy a whole home in good conditions at the 50k mark.
Japan follows the same trend, and yes, I've traveled Japan some, there's plenty of almost-ghost towns nowadays where you can buy real estate for pennies as well.