Legal Question in Wills and Trusts in Illinois

You do not state the nature of the incapacity (physical or mental). In any event, the executor does not have any power until after the testator passes and an appointment to the office is made by a probate court. If your mother has not granted authority under a valid power of attorney for property and is not able to handle her own affairs, then a court guardianship proceeding would be warranted. It appears that at this time you stand on equal footing to your brother (absent a power of attorney in place), but that trying to do anything could be troublesome. Since he is at the property and probably has more influence with your mother (if she comprehends and is able to express any say), your attempts to rent units may create issues as far as providing tenants with units without unwarranted interference. See a probate attorney about guardianship or, if a power of attorney is in place, about questioning the exercise of the authority under that power.