City house prices in the euro area and the US have not shown significant convergence from 1987 to 2008, despite similar national trends. Factors like income levels and population differences play a role in price variations, with income being a key factor in Germany, France, and the US. However, income differences are less influential in Italy and Spain once other factors are considered. Overall, city house prices in the euro area have been less varied compared to the US, with income having a lower impact on price differences.