Televised ducts under slab floor. Ducts are concrete ducts with metal fittings and connections that are rusting and allowing sand to enter the system. Suggest spin cast mortaring to restore structure back to metal joint areas then spray lining system with Duct Armor duct lining material. Also televised sewer from outside clean out along service sidewalk in front of house. Sewer is backed up at this time at 28ft. Suggest rodding to clear blockages.