Limiting a tenant's liability for rent under a residential lease to not more than 2 months' rent after the date on which the tenant vacates a leased premises if a physician or psychologist completes a form specifying that the tenant has a mental disorder that causes the continued habitation of the leased premises to be unfeasible or unsustainable and requires the tenant to move to a home, facility, or institution to obtain a higher level of care than can be provided at the leased premises and the tenant vacates the leased premises.