I don't think there are any short term solutions, but there are a lot of medium/long time things you can do.
One policy I have found very interesting is to require developers to "invest" in the neighbourhood in exchange for building permits.
For example, the government could require developers to pay for public infrastructure before they can build (eg. they need to pay a part of a new subway line, or they need to renew the sewer system etc.)
This helps address the problem that there is lots of capital available for building new stuff, but nobody wants to pay for maintenance.
One policy I have found very interesting is to require developers to "invest" in the neighbourhood in exchange for building permits.
For example, the government could require developers to pay for public infrastructure before they can build (eg. they need to pay a part of a new subway line, or they need to renew the sewer system etc.)
This helps address the problem that there is lots of capital available for building new stuff, but nobody wants to pay for maintenance.