> vacant properties sitting around empty because of money laundering and speculative usage

I don't have the numbers but I find difficult to believe that there's enough properties used for money laundering to move the prices.

> usage disparity because rural areas have been left behind by modern infrastructure

That's the problem. There are empty houses but too old or in places where people don't want to live. So to low the prices more houses need to be built there where people want to stay.

Another solution would be improve the communication channels between cities and rural areas.