Instrumental variable | house prices

[Max7]

Hello,

I am currently working on a panel regression that tests for influences on real house prices among the G-7 countries.

Independent variables: Rent prices, CPI, GDP, disposable income, savings ratio, unemployment rate, short- and long- term interest rates as well as a time series which is based on 13-quarter house price moving averages and proxies individual expectations.

Nevertheless, I am also looking for instrumental variables.

Any tips?

Cheers and thank you,
Max