Any person or entity aggrieved by a finding, determination, notice, order or action taken under the provisions of this section may appeal the same by filing an appeal. An appeal must be perfected within five business days after receipt of notice of any protested finding, determination, notice, order or action by filing with the City Manager a letter of appeal briefly stating therein the basis for such appeal. A hearing shall be held on a date no more than 15 business days after receipt of the letter of appeal unless appellant requests a longer time period. The City Manager shall give the appellant, and any other interested party, a reasonable opportunity to be heard, in order to show cause why the finding, determination, notice, order or action should not be upheld. Within 15 calendar days of the conclusion of the hearing, the City Manager shall affirm, overrule or modify the finding, determination, notice, order or action. The decision of the City Manager shall be final and conclusive.