Hi Neighbors!
Please check with your homeowner insurance agent and clarify what is covered and what is not covered. Maintenance is not covered. Roof leaks and pipe leaks are not covered except in cases of negligence.The insurance company makes that determination.
So, you may think your upstairs neighbor's insurance will pay for your damages if you are leaked on, but in most cases it will not.
Conversely, you may think you are protected if you leak into the neighbor below, but if it's a roof or pipe leak, probably not.
That's insurance for you!