If you have your own insurance that is the way to go. You have been told the correct thing. You need to show the people in the other apartment were negligent or you can't make a case against them.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 577-9797 or via email at Eric@RothsteinLawNY.com. I was named to the Super Lawyers list as one of the top attorneys in New York for 2012. No more than 5 percent of the lawyers in the state are selected by Super Lawyers. The above answer is for informational purposes only and not meant as legal advice.
Try your own insurance company. You can also sue the other tenant and the owner of the building. You have the burden of proving liability. You will need to prove what caused the accident by having an expert testify, the fire Marshall would be helpful.
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