This option is the least expensive option that would safely address what we were called out for. Filter rack will need to be extended to accept new filter. Current filter rack is 17 3/4†wide by 22†long. Customer is using snap financing. We were originally going to duct cleaning, customer approved for $2700. We are now only doing evaporator coil cleaning and IAQ 1000. Cleaned evaporator coil and installed IAQ 1000. Showed customer how to service filter.