First I would ask questions regarding the nature of the complaint that was causing the tenant to become irate and I would take notes to show I was really listening and trying to resolve his issue. Then I would attempt to gain his confidence and show that we would try to fix the problem and/or work to resolve his issue (within reason). If it appeared the tenant was not abiding by his terms of the lease agreement I would ask him to meet his obligation and the lessor would work with him to do its part if he cooperated so we could mutually resolve the issue in an amicable way.