From what I read, the problem may be the regulations that restrict buildings to very tight specifications. They (the builders) are also held up by permits and incentives to build. If there are rent and price controls on the properties, the incentive to build evaporates into thin air. What I know about RoI is basically from what I have read or seen in videos on YouTube. I have to say that the Guardia look like they are only guarding the ELites.