House prices play a significant role in how monetary policies affect the economy in Japan. When the government uses unconventional monetary policies to boost the economy, it leads to higher household spending, more investments in housing, inflation, and increased house prices. This means that when house prices go up, people tend to spend more and invest in housing. The impact of these policies can vary depending on the specific monetary policy in place, but overall, house prices have a noticeable effect on the economy, even when other aspects of the policy may not have as strong of an impact.