"Is there any chance that I'll end up paying $0.5 Million?" Do you have the money to pay?
You likely should review the facts with local attorneys.
Do you have any idea as to the cause of the fire? If the fire was your fault, you may end up being liable. Not only would the building owner be suing you, the other renters likely will sue you too. The damages may be a lot more than half a million dollars.
On the other hand, if you are not at fault, you may not be liable to anybody. You may even be able to sue the landlord if the fire was the landlord's fault.
If you are obviously "judgment proof", no one may be interested in suing you even if the fire was your fault as collection of a judgment would be difficult.
You should review your facts with an attorney to see what your options are.
I agree with the previous answer. You should try to determine the cause of the fire. Just because the fire may have started in your apartment does not mean the fire is your fault. The fire could be the result of something in the construction of the apartment, or faulty wiring or appliances. Consult with an Illinois attorney to protect your rights.
If you don't have insurance and are found to have been responsible for the fire, there is certainly the possability that you would be personally liable to the building and the other tenants.
You should most certainly not ignore the situation, but consult an attorney to ensure your rights are protected.