Came out to perform preventative maintenance on HVAC system. Met customer at front door and we began to discuss what brought me out to their home, the maintenance I would be providing and a couple of concerns the customer had regarding the system. Customer purchased home almost a year ago and has had upper respiratory issues since being in the home. She wanted an estimate on duct cleaning and wanted to discuss the filter situation. Customer had odd size filter grills in the home and had specialty filters made in order to fit them. They are also undersized for the tonnage of the equipment. Equipment needs 1600 cfm and the current returns only allow around 900. After doing an initial inspection of the return based, I found it hard to increase current grill sizes without redoing the entire base of the closet. There was enough space in the living room area to cut another small return. System had a filter internally that hadn’t been cleaned in awhile. I took it out and cleaned it. It’s a re