Legal Question in Landlord & Tenant Law in Illinois

Re: Landlord/tenant

Within reason, you guys can agree to whatever you want, if it's in the lease. If it's not in the lease, then it's sort of grey. I'd suggest that the occassional overnight visitor would not be a problem and a landlord counldn't do anything about it. But, if it's more like another person is living there, then if I were the landlord I'd seek higher rent or evict you for not following your lease.