Most of the Midwest and South are just as cheap as these places. Plenty of $600 a month apartments and $120k 4 bedroom houses in good suburban school districts.
Eastern Europe really isn’t that cheap because they had a 50 year period without much construction of private detached housing.
I checked out the small town my great grandparents came from in rural Slovakia. Prices were 50k for dumps and 150-250k for nicer modern places. These areas have declining populations so wouldn’t be good investments. If you want to visit, best to airbnb.