Floor level and building age show substantial imbalance between BTR and PRS subsamples. Both variables are included as regression controls, which partially absorbs these differences. However, the imbalance underscores that BTR and PRS apartments are not exchangeable on observable characteristics, reinforcing the need for cautious interpretation of the BTR coefficient. The building age imbalance is particularly notable: BTR developments are substantially newer than PRS comparators, and the BTR dummy may partly capture a newness premium rather than an institutional ownership effect per se. Future research should consider matching-based approaches (e.g. coarsened exact matching on age and floor bands) to improve pre-regression balance