You can look up information about your legal rights online. www.illinoislegalaid.org has information on a full range of issues. Prairie State has its Renters Handbook available on its website at www.pslegal.org.
Unless Cooling and Air Conditioning was included in your original lease you would need to buy another air conditioner. The size of your apartment may require a second air conditioner to stabilize the airflow in your entire apartment and provide you with more cooler air. Illinois owners are only required to supply heat during winter months.
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