If a village hires a firm to help lower the assessed value of properties subject to a special assessment but then drops its plans for the assessment altogether, should the firm get contingency fees for reducing an assessment that never occurred?Last week, a state appeals panel said yes — finding this move amounts to a 100 percent reduction in the would-be assessed value of the clients’ properties.The underlying litigation started when the village of Bensenville filed a petition in DuPage County Circuit Court in …